I don't know if anyone can help me with this but I am at a loss. When I enter the Warhammer 40k Space Marine at the main menu I can move my mouse just fine wherever I want but as soon as I enter actual combat gameplay my mouse locks in to a certain part of the screen and I have very limited movement of Titus only within that area. Sometimes as I'm moving the mouse suddenly the game starts to restrict me further and I can't move the character view as far to the sides as I was able to just a few seconds ago. When I pause the game I can move the cursor around just fine within the menu with no restrictions but as soon as I unpause it I'm back to restricted movement and views. Sometimes the mouse is completely locked and I can't move Titus's view at all.

I wonder if this is a prior reported bug and maybe there is a fix for it if that's the case? Can anybody help me there isn't a fix?

Update: Well I seemed to have figured it out on my own but I will post the fix that I found for future players that may run across the same problem.

I run my copy of Warhammer 40K Space Marine on Linux under WINE. I didn't put down this information earlier because I didn't want others dismissing my request for help as soon as they saw my specs.

I had the mouse problem and found somewhat of a fix by maxing out the horizontal and vertical mouse sensitivity settings in the options but my mouse would still lock up eventually and I would have to spin my character in a funky up and down twirl in order to free the view up again only for it to repeat several seconds later. I had installed the game under a older Windows WINE Prefix which was probably WIndows 7 and didn't think that could be a problem until for another reason I reinstalled the game on a Windows 10 prefix and to my amazement with both mouse sensitivity settings maxed out again the problem was solved! My movement is unrestricted and I can twirl around without the mouse ever locking up again.

To all Linux WINE players: Install the game on at least a WIndows 10 prefix and max out the horizontal and mouse sensitivity settings located in options. Also if your graphics appear blurry or phasing in and out (especially at the main menu and during cutscenes) turn off ambient occlusion also in options.