Steven P according to documentation "not filling up temp folder each time this runs" if you use VL MKtemp on closing Autocad the temp files will be deleted
As a 2nd make sure I use
(unload_dialog dcl_id) (vl-file-delete fname)
Ok so if you bomb it out yes file can still exist, so from a cleaning up point of view I have my temp directory set to my D:\Acadtemp and run a bat file every now and then to delete file yes .dcl will be there. Have a look at your temp directory you may be horrified how much junk is in there. SV$, BAK, etransmit to mention a few. At my old work I cleaned mine had a look at some one elses PC had like 2GB of files.