Masks aren't working, are broken

[Masquerade]

Yesterday, suddenly my masks in arc.groups stopped working completely. Some work, but it's seemingly random.

Here's my example:

I make my arc.groups completely empty, fill it with:

$bin
*.exe
*.dll

Now, if compress with:

-mx64zlib+srep+lolz/$bin=rz

The mask goes first and the exe and dlls are grouped in the command window, but when they should be compressed with rz, the arc just keeps on going, grouping all the files not part of the mask with it:



This leads to everything being compressed improperly.

Another example, we add:

$mp3
*mp3

-mx64zlib+srep+lolz/$bin=rz/$mp3=mpz

MPZ will run, but then everything gets compressed with MPZ!

Just a note: above game has no mp3, I know, but this is for every game I try!

I am so confused and I am at a total loss..

Please can anyone help?