Sorry for the double post but when you change a texture through the main window, the main window never updates. Instead, it looks as if you never changed the textures at all until you deselect them and select them again. I found that to be heavily annoying at first.
Suggestion: Color the lines of a sector which are tagged to an FOF or any other sort of linedef action. I found out that sectors which were used only for FOF with no other changes were marked in the zero difference color. I found this both annoying and useful. Annoying because the color the zero difference linedefs were made it hard to tell the FOF was even there and useful because when I set zero difference linedef colors to a much brighter color, I could tell it was an FOF immediately without having to remember or check. Thing is, I'd like to keep my zero difference linedef color to a dark color. So I think coloring tagged sectors without having to hover over the linedef that it's tagged to would be a great idea, whether it's colored always or only when you hover over it. (Both of which is good.)
EDIT: Okay, I kept trying to use the texture changing in the main window thing and I found a whole slew of new bugs. 1) Sometimes certain textures won't change. I had a linedef with a front upper texture a back upper and lower texture. I attempted to remove the upper front texture, change the upper back texture then remove the lower back texture and lower back texture refused to change. Further more, when I changed it the old fashioned way, it labeled the texture as "Missing" when in reality, there didn't need to be a texture there at all... 2) Selecting a lot of linedefs and attempting to change the texture sometimes doesn't change all of them. I haven't found any pattern to that yet. 3) Trying to change a linedef's texture too much will result in the linedef unselecting completely...but you can't tell because linedefs are still red (or selected) and the detail display never changes, though you can't interact with it at all. It's only noticable when you hover your mouse over one of the linedefs, that's when all the lines "appear" unselected and the detail display changes. Your last texture change isn't saved either when that happens. It appears to be connected to the first bug mnetioned in this edit.
Another final thing: DB keeps pestering you about the Control Sector Hint Thing being outside the map when most of the time, it
should be outside the map. Not really a bug but it's quite annoying.
By the way, I can't say for sure about this but one time, I tried making a sector normally, but DB ended up
reversing the sidedef pointers. For instance, the one linedef had it's front sidedef pointing to sector 31 and it's back one pointing to 33 but the pointers were saying that the front one was pointing to 33 and visa versa. I only did this once and haven't been able to recreate it but it was very strange nonetheless...
'NOTHER EDIT: Alright, another suggestion: Redesign the testing config for SRB2. For instance you could specify what map type a certain map is in the Map Options (Which of course could be saved in the DBS file) and when you test your map through the test key/button in DB, it'll use that map type you specified to determine which parameters to start SRB2 with so you'll always test your map in the correct gametype. This way there's no testing maps in Single Player and such. You could even have force keys where you could force a certain test mode regardless of the map type specified. Example: One key tests the current map in Match while another tests it in Single Player and another tests in CTF. I suppose you could also add check boxes, radio buttons and such in the test tab in the main configuration dialog box for options like music and sound settings, windowed mode, open gl, which skin you want to use, devmode, whatever you think would be handy for testing. You've made a launcher before so I assume this would be no big deal to implement but if you feel it's unnecessary then you don't have to put it in. ^_^;; I just think testing is a very, very important process of designing and building and it should be made as effortless as possible if you're going to be testing a lot.
EDIT: Yes...another edit.
The control sector hint thing fails. DB tried to follow it but puts the control sectors so close together that they OVERLAP with one another, and create a whole SLEW of problems. I had to spend a half an hour trying to fix the abomination it created. It makes the FOF dialog unusable.
EDITv4: Sigh...another edit. One thing I've noticed over the past year I've been using DB is that it has a very hard time distinguishing what sector is what. For instance...
Let's say the red sector is sector 1, the green one is sector 2 and the blue one is sector 3. Let's also say sector 1 isn't drawn yet so I draw it counterclock wise. DB gets confused with sector 1's linedefs merging with sector 2's linedef and thus,
thinks that sector 1 is part of sector 2. This results in sector 1 sharing the same properties as sector 2, the linedef connecting the two sectors having wrong sector references and multiple "sector not closed" errors. Further more, no matter how I draw sector 1, sector 3 will be inside it. But
DB does not fix sector 3's linedef references once sector 1 is drawn. Sector 3 still thinks it's part of the previous sector it's in, resulting in even worse unclosed sector errors. You see the problem here? It makes drawing sectors very hard when you're dealing with a lot already.
Furthermore, moving a sector inside another also does not fix the linedef references, making it impossible to put an existing sector inside another without having to edit the references yourself. Moving a sector next to another, trying to merge the linedefs of the two sectors, will also confuse DB and mix up more linedef references. I must say, DB has gotten quite buggy as of late...