I'll post new comments here as they become relevant and as I start researching them. I'll post each topic separately and edit them when the solution is found, if necessary.

1. Having a TON of maps with objects will bloat the the save file enough that the AutoSave feature in TTS will take a while to finish. This can lead to a framerate dip to 0 for a few seconds every 5 minutes or however long you have that configured in TTS. This only starts becoming an issue when you have hundreds of maps with objects, but it's something to remember.

2. There is a problem with the 'SYNC' functionality in OneWorld where it breaks objects with multiple states. If you save objects with multiple states into a map and then press the SYNC button after they are built, transitioning to the other states will throw an error stating the object is invalid because the scale is NaN. I haven't looked into why this is yet, but i'll edit this comment with details when I do.

3. When you need to rotate a map to make it horizontal, don't rotate it with windows. Use an image editor like GIMP to rotate it. Windows and some of its apps just add metadata to pretend an image is rotated instead of actually rotating it. TTS ignores this metadata so your images wont rotate on the table.