You can also use calculated fields to filter the data instead of the build in row level security. Apply the field at the "data filters" level.
If you have trouble with blending this in - you might try using the table to apply groups to the user. It would definitely by easier to do a ISMEMBEROF() calculation.
Hope this helps!
Thanks Derrick...along with your advise and some other workarounds I was able to pull it off.