It might help if you had some kind of established workflow of some kind that has been successfully used by many other mappers.

Depending on what version of FT you are using you may might have access to the One Day Worldbuilder pdf. It comes free with FT3.5. Even if you are still using FT3 you could download and install FT3.5 just for the pdf. The download should be available under the same group of files on your Downloads tab when you log into your account on the main webpage.

It's a pretty long read (though actually its mostly pictures), but there is a supplemental notes pdf that covers creating your own world from a blank world, such as you are doing right now, and it was written for FT3.

Without transferring files (FT3 files are simply enormous), you might want to look at that for a basic workflow, or at least to get some ideas about how to solve some of your current workflow problems. You won't need to do all the last bits of the process which are concerned with transferring your world to CC3 for CC3 mapping projects.

This is just an idea. You don't have to do it that way if you don't want to.

As a plus, the One Day Worldbuilder will show you how to take your world from FT3 to a really handy piece of free software called 'Wilbur', where you can play with erosion, and then bring the file back to FT3 again.

EDIT: sorry - no Discord that I am aware of.

You're correct. These are files you can put anywhere you like on your system.

You have Transparency Acne with the fills that are more or less identical to the Land texture bar some inking. That is where the render engine gets confused by pixels that are identical to the pixel on the underlying sheet and discounts it as being transparent. This creates a tiny 'hole' in the overlying polygon to which all the sheet effects are then applied the same way as they are to the outer edge. So from a percieved pinhole you get a very real edge-faded hole - acne.

There are a few different ways of dealing with it but the easiest one in this map is to use what I call a 'backing sheet', where you place a plain polygon underneath the top one by copying the problem polys and their sheet effects onto a new sheet between them both and changing the fill of the new polys to some solid colour that is sufficiently different to both textures that the render engine understands there are no holes in the topmost polygon.

I hope that makes sense.

I've created just such a backing sheet in this one for you:

Yes. Jim is correct. The first thing I do when I get a problem map is use List from the Info menu on the problem polys or symbols just to see what sheet and layer everything is on. I could see there was a duplicate because the count in the command line was instantly 2 instead of 1 object selected. When I pressed D for Do It the information for that red poly came up twice - on two different layers.

There are two identical red polygons on the WALKWAYS sheet. When the 3 of them are multiplolied together you get the two red ones cancelling each other out except for an outline. Fortunately these two red polys are on different layers, so if you hide either the "BACKGROUND (FLOOR 1)" or the "BACKGROUND (FLOOR 2)" you can use just one of them to multipoly with the blue shape.

Unless you really want both of those red polygons I recommend deleting one of them so you don't get this happening again.