There is def something messed up with your recovery, either that or with the process you're using. I've never heard of a properly rooted Droid not being able to flash anything. Your best bet would be to flash the stock, unrooted sbf file for 2.2.1 and reroot.
Maybe a stupid question but you do have a Verizon droid1 and not an A853 milestone right? These roms and kernels will only run on Verizon droids and A854 milestones
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