This guide is made to pool all the issues, for pc, in one place and hopefully some of these issues get resolved. If you have some things you want to add please put them in the comments and I will add them when I can. Thank you ahead of time for your input, it helps plenty, I will admit I do not know everything and by you addressing the issue; I will append the mistake and everyone benefits.

UPDATE: Some features have been since patched and if something on this guide is fixed please notify. Thanks and happy building.

UPDATE 2: ATTENTION TO ALL WHO WILL POST QUESTIONS HERE!
Please go to the forums first and ask, because I am not a developer or an avid player, I only played and completed this game once and did not find enjoyment like the original Lego games from my childhood. This was only created because I played and found a bunch of issues and things I felt should have been seen in testing like getting stuck in the shop/relic screen.

Reason: Did you try to scan something and it did not scan regardless of position?
If 'Yes' then that was the cause of the crash.

REASON: You fatfingered the 'windows' key.
SOLUTION: Hit the 'windows' key again.
EXPLANATION: For some unknown reason when the windows key is pushed it does not open the start menu and keeps the game up but it acts as if the windows key is always being pushed and then pressing the d causes the screen to close.

-The 'open all' feature.

• RMB does not work, but on a controller works fine.

fixed
-Playing the Flaming guitar.

• Says to press Number Pad '0' but that does not work Press E

-Changing the video settings while in game. (Not main menu)

• They only function in the main menu for some strange reason.
  
• Update: not tested as of recently.

-Saving your characters

• On next play they will be blank.
  
• Correction: they do save it just takes a minute to load.

Essentially the screen minimized and when you reopen the game is zoomed out and in a tiny window. The solution to this is to force close and restart.
Then go into options and fix the resolution the best you can.

Self explanatory.
Solution: Open the world map and re-enter the world.

Apparently there is an issue. You get stuck after phase one. So here is the fix. Thanks to Kireev20000
If that doesn't work try this from Bob the Gigglemaestro
1) Have your graphics set on the LOWEST setting
or
2) Jump into the air before the cutscene triggers.

OR
Ares: i managed to get back into the actual area by running and doubling jumping just right at the corners and then on the vacuums that are on same spot there is a barrier at back of the one i went to and manage to jump onto it and slide across to the legit play area without the vacuum picking me up and killing me.

GOOD LUCK.

You open a relic and are presented with a blank screen?

I have come across this many times while opening mega relics.
The solution is to open a different relic if you are on shard 4/5. Thanks to user Owlsea, they have figured out why this happens:

• "on Xbox, getting the mega-relic store freeze bug. I've noticed that it only happens if I have 4 of 5 Mega-Relic Shards, and open a Mega-Relic. This causes the 1st duplicate to create an additional Mega-Relic, and this seems to be when it freezes. It also happened to me when I had 9 of 10 Super-Relic Shards and opened a Super-Relic.
  
• I've managed to avoid the bug completely after figuring this out. If I have 4 of 5 Shards, then I open a Blue, Green, or Purple Relic to get another Duplicate to get another Shard, which makes a New Mega-Relic.
  
• If the number of shards is 0, 1, 2, or 3 it's fine, and I can open the Mega-Relic without the bug. For the Super-Relic, I just collected another shard from a chest, so that it was no longer 9 of 10. Hope this helps on PC too."

Another issue is when you do collect a relic you may be presented with a star that is blank and above it says “CURRENT_RANK”. Thanks to eatboxtv, they say to go to the minimap and expand it and then go to galaxy map.

Do you want to play somewhere else?
Thanks to dr. wachtel king.
-It has been brought to my attention that the data was not in the place I had originally posted. He says:
The save data is stored by default at %APPDATA%\Warner Bros. Interactive Entertainment
(%APPDATA%
Contains the full path to the Application Data directory of the logged-in user.)
Copy the folder named "LEGO The LEGO Movie 2".


Secondly, just to be safe grab all of the files in the folder and copy them onto a stick as a backup. Then, use that to move them into the corresponding folder on the other PC and do this every time you want to change PC and make sure both PCs are the same.

Tip #1: If you acquire the super magnet you don’t have to risk brain power to reach chests. This is because if you can shoot the chest and pull the magnet out it will grab the bricks, studs, and relics.
Tip #2: Always dive down you may find a chest or a special block.
Tip #3: If you have the weird sucking aliens on you and you hit ‘tab’ they will detach and you are safe because the ‘e’ key does nothing.
Tip #4: You can cheese most climbs with either another object or with a structure. For example, in the forest there are tower ruins with a block on top, you can position yourself and with timed jumps make it to the top.
Tip #5: Scan everything. This is because you may not know what will be needed in the future. For example, on the asteroid, before climbing a cliff and facing off with some astronauts in black suits, there is a tree that apparently is for a quest. I don’t know where but it was in that category when I was building something else.
SIDE NOTE: You may crash. But if you do just don't scan that object in that spot again next time.
Tip #6: by Akira Onoo
If you mash A with the Jetpack, you’ll run out of gas slower. It’s something I call “Mayhem Pumping”
--------> PSST. This is helpful until you find the mega item relic variant.
Tip #7:
If you don't know how to continue in a world because there is an item you don't have just play the story missions and beat the game. Then, go back and complete the other missions.

HUGE TIP:
The best relic to buy is the green one. BECAUSE they give 3 items and after a while of opening the relics you will have almost everything and start to get Golden Mega Relic Shards. Then, The GMRS turn into Mega Golden Relic and those always give new stuff. So then logically, your chances of getting a GOLDEN MINIFIGURE are amazing. Plus the ability to get other good stuff like flying vehicles.
EDIT: This does not matter when you have 400 blocks collected. You will see why.


IRONICALLY my first Gold figure was Emmet

and my first shimmer was Wyldstyle (Lucy)

Funny little side note. If you sit in the harmony planet shop and the screen is angled slightly looking at the wall with the sun there will be a point where the npcs will start respawning and on the edge of your screen there will be a pileup of characters. I WANTED to take a photo of it but after I got my Golden Boi, I opened another 2 relics and the game held me hostage.

In the image above you can slightly see the pileup on the left and the duped NPCs on the right.
I was also supried to find this upon my first visit to the planet: