Traffic++ Pedestrian *Roads* will not connect to vanilla Pedestrian *Paths*, which is what custom lots will contain, however if you drag a pedestrian road up to a path so that the textures connect, pedestrians will walk through.

I have also noticed that the No Pillars mod features do not work with the custom road types added by traffic++.

Pedestrianised Roads and Pedestrian Paths are two completely different things - you can connect paths to roads (any roads) but can't connect roads to paths (any paths), this is just the way the game is coded unfortunately :(

Regarding NoPillars mod I use that mod extensively and haven't had any problems with it on the custom roads - is there a specific road it doesn't work on / or what is the specific issue that's happening?

I've noticed that the "overlay" (no collisions) doesn't work properly for any of the custom roads added - for example I am able to place a park under an elevated vanilla road but not a traffic++ one.

Will see if we can get that fixed :)