I have a couple of thoughts on this... one, the transformer saturation issue can be helped by using a lower voltage than the nameplate voltage, EG if you could tap the transformer at 110 rather than 120 volts.
Also, are you SURE it's 220 volts? if you have a transformer to produce 120v from 220, if it's plugged into 240 volts the output will be around 126 volts which may be over tolerance for many appliances, especially in conjunction with the lower frequency. (just a few ideas
Another thought, many manufacturers slightly overwind transformers, so if it's rated at say... 1 kva, 120volt, at no load it may well output 125-130 volts (the regulation on small transformers tends to be lousy)
[This message has been edited by chipmunk (edited 07-23-2004).]