You can use TOFFSET in a macro, but it is a bit tricky since it uses single entity pick instead of a regular selection. Means you cannot select with prior, but you can select it if you know the coordinates of the entity (But these are tricky to get for an entity drawn with a drawtool)

Depending on the kind of offset and lines you need, the double lines [DBLN] command may be easier to use in a macro.

You can't put symbols along just some of the edges of a shape. Symbols along will put them along all edges. I guess you can write a complex macro that figures out which are short and long edges, and calculates positions and puts symbols along them, but that is getting a bit complicated.

To make lines that doesn't change appearance as you zoom in/out, make sure they are using line styles that do not have paper scale enabled:

To align fill in a drawing tool, check out the macros in the Garden tools in the Annual Ferraris city style, it does exactly that.

The master filter is loaded in the OnOpenMacro map note in each individual map. (The SYMICONFLOAD command)

Sounds like an interesting, but also very difficult project. A CC3+ map is just a few bits of text really (stored in a binary format) that describes the layout of the entities in the map, so that means that unity would basically need to implement the full render from CC3+ to be able to turn that information into a visual representation of the map.

Lee started talking about the .fcw file format here. Unfortunately, he never finished the job:

While CC3+ itself allows for almost infinite scaling, the symbols and fills themselves are still ordinary raster images (To get the most out of the infinite scaling, you would need to use vector artwork instead of raster, but generally that's not as pretty, and while they scales indefinitely so you avoid pixelation, they aren't detailed enough to really look good when enlarged too much). The raster images provided in much higher quality than you would ever normally need, thus allowing you to export the map at quite a high resolution, but there are limits. Try opening up one of the .png images (you'll want top open up the _VH version of the file) from CC3+'s symbol folder in your favorite image editor, and zoom into it, and you'll notice that you can make it quite big before pixelation becomes an issue.

No. The pixelation is a limit of the resolution of the artwork, so the only thing that really affects that is how large (physical size) you make the final output, there are no way to cheat in CC3+ to affect this, it can't make the images better than they are.