I play in window mode with all variants of fonline(Fo2,AoP,TLA) and on the TLA sdk rev 455.I've no problem with Fo2, AoP and TLA(fonline.ru) that glitch happen only on the sdk...
Are your graphical settings the same in SDK client as with those other games? Verify that. Also try deleting the cache so it can be recreated, it may help, but I doubt it.You could also try updating your graphic card drivers as a last resort...
Fixed in revision 456.https://xp-dev.com/sc/change/76003/456