(disclaimer - I'm putting it here due to small activity on game's sub-forum)

I was trying with dgvoodoo and dxwnd, but in both cases it doesn't help, game is still running in full screen. I was checkinig the nglide file inside the game's folder,but there is no option which would suggest such possibility (tried with changing resolution and aspect ratio, but it doesn't help)
https://i.imgur.com/1hL258f.jpg

Disclaimer - I was trying on both DirectX and 3DFX settings, but in both cases I had no luck.

With kind help of gro from DxWnd website I was able to launch windowed Incubation through DxWnd.

I'm still curious though if similar thing is possible with dgvoodoo or nglide. If by any chance someobody had success with any of these, please share with me your method ;)