What I've found is that I have to reload GAPPS most every time I install a new ROM onto the Touchpad. If I don't it will often, but not always, not allow me to log into any Google services.
So.... my typical process is to install a new ROM, re-install GAPPS, clear dalvik/cache, and then boot into CM9.
On mt TP, the version of GAPPS I've been successfully using is
I had a version of GAPPS with a May date on it but it didn't work reliably for me.
Yea though I walk through the Valley of Google I shall fear no Apple...
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