There seems to be no way (on systems with case sensitive filesystems) with SysFileTree of finding, for example *.jpg where "jpg" could be in any case.
The only mechanism seems to be to search for . then select the files that match *.jpg in REXX itself.
This can be very time consuming.
I would suggest adding "I" to the SysFileTree options, implying case-insensitive matching, in the same way that "I" implies case-insensitive sorting in SysStemSort.
Doing in SysFileTree should be faster than doing it in REXX.
I've been asked why the files are in varying case in the first place. They've been deposited in a public directory from a variety of case-independant systems, so we have no control of the case of the files.