Tested with:
Clean cmpro4.35 x86 or x64 , take exe from the forum build and replace over 4.35.
Create folder "1" and add inside first mame dat: mame0204-179-ge754e43586.xml,
load dat , all warnings and etc etc, do not load roms folders, samples .
Open scanner window and close scanner window and back in Profiles folder .
Atm all is fine , looking "1/mame0204-179-ge754e43586.dat"
Now create new folder "2" and put dat: mame0204-199-g4345e8d455.xml in folder 2 .
Now have "[NEW DATFILES] 2/ mame0204-199-g4345e8d455"
double click over dat and next window "No Settings Found" click Update button, next window "Update Settings" check "1/mame0204-179-ge754e43586" and Update button .
Again load dat , all warnings and etc etc., open Scanner ( do not start) , close scanner and back to Profiles folder and see problem :
have two folders "1" and one folder "2"
first "1" it's empty
second: have dat
"2" - of course is empty
Never see this problem before .
From many years ago i used this method for update mame dats :
Drag and drop dat in any folder ( not looking )
and with dialog windows "No Settings found" and "Update settings" updated old dat .
Hope u understand me

P.S.
Noticed , if start the first time cmpro and create folder ( not loaded dat ,nothing ), folder it's not see.
When add first dat i looking folder.
Do not remember that bug or cmpro features.
