Irfanview, and XnView will open PCX and DDS files (all decent progs do). Just export them as DDS (it is just a file-format and you don't need anything special to "edit" it), then you just need to open it then save it to PCX for UEd2.
If you must do a screenshot, Irfanview will also allow you to grab the contents of a window, rather than the whole window or screen.
8bit PNG would be the preferred option for uploading individual skins here, as the moment you turn them into a JPG you trash the original palette (they will also be smaller)
Texture packs are also more preferable than "MyLeveling". Far easier to manage, and swap around with alternative versions while testing. That way I can work on a low, medium, and hi-res version of the same textures at the same time.
1 map, 3 texture-packs, depending on how big you GFX card.My map U1 edits at the moment have a 256x256, 512x512 and 1024x1024 textures. You pick what suits you (I use the large ones). This is the standard I will be sticking to for U1.
This also allows for easy creation of optimised server-only mini textures, should you want to include in a distro.




