CGR is a Catia GRaphics file.
Solidworks can read some versions of these files, but not all.
For instance, it is not able to read *.CGR files produced by
CATIA v4 4D Navigator (and many Catia v5).
However, it is able to read files exported by himself !
It seems the cooperation between DS companies is not full...
They are not much use anyway (or at least did not used to be). I think all you get is some surface topology of dubious accuracy. This being due to the "graphics" approximation in CATIA. We always use regular CATIA files (both 4 and 5). (And use Cadverter custom conversion software).
General Note: Things go into CATIA very well, going the other way can be interesting with complex goemetry. This is due to the different floating point accuracy of the databases. When dealing with surface equasions, SW uses more decimal places before rounding off and calling it good. BTW: Any ACIS based systems also have the same problem verses Parasolid based ones. There was a good presentation on this subject at SW World #1 if you can get hold of a copy of the proceedings.
3/4 of all the Spam produced goes to Hawaii - shame that's not true of SPAM also.......