Re: Transfering Ranks Between Schools
I wouldn't be too fussed if you're a 5th kyu as was mentioned (though at 5th kyu everything always seems like a rush). Different places/teachers have different ideas how to deal with it and a lot of the time, in my experience, its been the sensei who's determined were you fit in the system. At 5th kyu its likely you'll start again, though if I could find my Yuishinkai handbook someplace I think it says they recognize rank from other styles (you just have to move forward with their requirements), if that's the case you'll at least transfer back with any rank you earn at another dojo.
When I moved to Yuishinkai, my teach spent a while evaluating me and after a while decided to have me grade to the rank I left the old organisation at (1st kyu), I was just planning to start again as it had been a while between drinks for me.
At the moment I'm training at an Aikikai dojo in the US, in this case I haven't joined the federation as I intend to return to my dojo in Australia in a couple of years, a period I wouldn't have graded in anyway. I offered to join but was told it wasn't necessary if I wasn't going to want to grade with them. This might be another option if its only to be 6 months or so, and returning to you current dojo. You wont grade but your Aikido will still grow.