Under normal circumstances, yes the game will be just one .exe file. You can however load sounds and graphics at runtime from folders if you like.
Also, there is really no set file size limit. Obviously you need to keep in mind system limitations, and whether or not someone is going to be willing to download a 130MB game, etc. You may want to check into some optimization:
- Don't import large graphics if you're just going to scale them down in-game. Import everything at 1:1 ratio
- Trim any excess from around the edges of your images. Also keep in mind the power-up rule... if your image isn't sized at a power of 2 then it's going to be scaled up in VRAM. If you have a 34x36 sprite, it's going to be taking up 64x64 in VRAM... so perhaps you could find a way to just redraw that sprite at 32x32?
- Compress your sounds! A lot of people skip this one. Make sure all of your sounds have decent compression on them, and that all blank space is trimmed up. Some people think they need the best sound quality at 44100Hz sampling rate when they could easily get away with 22050Hz. Don't use WAV whenever possible
- Are you using tiles wisely? Can you break up any large images into smaller components that you can use as building blocks? And no I don't mean just cut up large images into squares. I mean is there, say, a tree in your image that repeats multiple times? If so, why not just make a single tree sprite and paste a bunch of copies?
Check out more optimization tips on the wiki:
http://sourceforge.net/apps/mediawiki/c ... ation_tips
However there may be an issue with VRAM and resources not loading properly on a layout to layout basis, but somehow loading all at once, which could be more noticeable with large projects. Kayin discovered it, and David was looking into it. I'm not sure what all the details are yet.