Here is a script I wrote to turn on cropping for all bitmaps - usage is pretty simple - you can apply it to a mat library - scene mats - selected object's mats or materials in the ME. Checking 'Reset UVWH' will reset the UVWH cropping dimensions only on materials that do not already have cropping applied.
See comments section for information on how this can help resolve a bug in max 7 and vray!
NOTE: 12/10/04 Fixed error message generated from incorrect .mzp file...
This bug - which was fixed in 3dsmax6 - has returned in 3dsmax7. Under certain conditions - on objects with UV coordinates outside the [0 -1] range - the 3dsmax bitmap texture plugin can return a random color from memory. If this is a negative color - or too bright a color - you may get colorful splotches in your scene. GI can propagate this effect through the whole scene making everything in vibrant colors (red - green etc).
The solution is to check the 'Apply crop' option for bitmaps in the scene.
As with 3dsmax5 - we will post a recompile of the bitmap plugin that fixes this particular issue and we have also notified the 3dsmax development team...
Best regards -
Until the recomplile - get my Apply Cropping Script - it will save you a lot of time.
To install download the file - drag it to the MAX viewport and follow the instructions (make sure when you download that the extension is still 'mzp')