Digital BW, The Print

Any tips for getting the R220 to recognize 3rd party carts?  I'm using the MIS UTR2 inkset and 
when I last ran out of cyan, it refused to accept either of two brand new MIS carts. in this 
position.  I tried the things MIS tech. support suggested (shimming, pulling the power cord 
during cart replacement, bending the tabs, overstuffing the chip cavity), but nothing seems 
to work.  In desperation, I threw in the OEM Epson cyan cart which it took just fine (so at least 
I can print BO for my next photo class assignment).  Anything else I should try?  Thanks in 
advance for any help...