Problems savegame bugs are not resolved in this version, my guess is that they are related to video card driver, some players have no problem. I searched for ways to improve things on my pc (Win7) and I give you some ideas that may help but will certainly not be valid for everyone.

On my PC I was playing with a resolution of 1680x1050 and I had many crashes. Playing with a lower resolution, 1280x800, crashes have disappeared.

To change the game resolution to use the file "Shortcut to Tomb4" but you need to make some adjustment for the files that point to your PC.
Right click on the file and choose "Properties". You will need to change the folder "Target" and "Start" to match your gaming file

To replay a savegame that crash, a method has been proven on my PC.

When it is possible to reload a savegame Windows 7. Put tomb4.exe in compatibility mode Windows 98. Restart the game and reload the savegame. Then make a new savegame in one place. Then we can replace the Windows 7 tomb4.exe mode and resume his savegame. On my pc (W7) this walk each time, I hope it will be the same for those who use this method.

Little explanation to switch to Windows 98 compatibility mode.
Right click the file and choose Tomb4.exe "Property". Click on the tab "Compatibility".
Check "Run this program in compatibility mode for:" in the list below select "Windows 98"
Click Apply and OK

To return to Windows 7
Uncheck "Run this program in compatibility mode for:" and click "Apply" and "OK"

Some will tell me, why not leave it on 98 ?
If the finesse and the screen resolution mode Win98 you, this is the best on my PC is really bad, the resolution does not fit my screen at all.

Otherwise the advice I can give is to never make the savegames in one place, the latter may crash but not before, shifting the savegames you will not have to replay the whole level!