DrIstvaan: It's curious then why it's like this for me then. For me, it is really small; when I have some effect active, I can barely see its icon.
I've made a screenshot of WinROTT, it is very messed up (it looks like some disco fever-induced painting), but you can see how narrow my status bars are.
Which version are you using and is it plain WinRoTT or WinRoTTGL (GLRoTT)?
I've had a look in the game settings both in the game and in the WinRoTT client before you launch the game and I can't find anything that might alter it, so I could only suggest changing the screen size in-game (like the old FPS games used to with +/-). Other than that, maybe send an email to Birgers to see if he knows what causes it and whether there is a fix.
I've provided a photo (couldn't figure out how to take a screenshot) of mine running and you can see the bars just as they used to in DOS. The textures are unaltered so up close they look just like the old DOS days, but they keep their detail at further distance due to the higher resolution.