It depends on exactly what sort of yeast you were using, but odds are that those temperatures would have been bad, but not entirely disastrous for your beer. It'll certainly have lots more fruity aromas and flavours (from esters) than a typical alt, which would usually ferment at a temp more like 60F.
Alts are usually lagered (cold conditioned.) This helps clean up some off flavours and helps clarify the beer. Lagering is one of the things that makes alts as clean tasting and smooth drinking as they are. Using a secondary for lagering is a probably a good idea. Leaving it on the primary yeast for another 2-4 weeks will probably not result in autolysis and off flavours, but using a secondary will probably give you a somewhat clearer beer (in this case at least. Lagering is one of the only reasons I use a secondary myself.)
That said, I'm not sure if lagering your beer is really that necessary. After your fermentation temp problems, you aren't really making an alt anymore anyway, so it's not really necessary to follow the traditional process for one anymore.
An interesting idea might be to bottle most of it and put 1-2 gallons in a smaller secondary and use your usual fridge to lager it. That way you'll open up your primary fermenter for a new batch sooner and you'll get to learn a bit about what lagering does for a beer.