Never mapped caves before but this is what I use for mapping the surface:
http://research.microsoft.com/en-us/um/ ... s/ivm/ice/ - Free download from Microsoft. Binds images. Really easy to use. Works really well producing accurate composites.
http://www.irfanview.com/ - Image viewer with a load of advanced features.
1. Use IrfanView to continuously take screenshots at an interval of a few seconds.
2. Use IrfanView to batch crop all the screenshots to remove the interface.
3. Select all the images and drag and drop them into MS ICE.
4. Once it's processed them, check that the mode in the bottom left is Planar 1. If it is on one of the others, select Planar 1 and it will process and bind them again - hopefully correctly this time.
If you have problems with ICE not binding images correctly, reduce the number of images that you are trying to bind - Do a few, export (PNG for lossless), then bind the exported composites.