mouse accuracy+speed / srb2dd, why isn't libgcc_s_dw2-1.dll included?

Note
It's easier to visually detect this effect in first person view.

Issue
Standing still and moving the mouse 180 works as well as any other game.

But holding down a key (like W for forward) diminishes mouse accuracy and turning speed; it's apparent even if W is unbound.

Description
I have to move the mouse a greater distance (slightly greater, but noticeable to irk me) to turn the same 180 degrees.

Camera steering pauses intermittently even as I move my mouse at a constant rate.

I have experienced this on multiple (Windows 7) computers, doesn't matter if keyboard and/or mouse are 'gaming' or 'non-gaming' types.

What exe are you using? Srb2win or dd?

srb2win (tried both software and opengl), dd doesn't run for me.

Srb2win has inconsistencies when it comes to mouse sensitivity. Im not exactly sure why but this has been mentioned before.

So, I'll have to try getting srb2dd to work;
paying attention to the error pop-ups this time, it says libgcc_s_dw2-1.dll is missing and thus r_opengl.dll cannot initialise.

I could try getting it myself from https://www.dll-files.com/libgcc_s_dw2-1.dll.html, but it lists two dll files, one is 105kb when unzipped and the other 109kb unzipped; odd.

Edit: oooh... dd is deprecated. Was mentioned 2.2's srb2win will get srb2dd's 'smoother frames' from then on (does this mean, fixed mouse too?), and that srb2dd will be removed for good.

I think i fix this issue

Just go on Srb2win (windowed mode) and put the Fullscreen off in the videos options.

This should fix the over sensitive Mouse movements