A "word". The file name is like this: AAAAaaaaaa-NNNNNNNNNN[N].XML, where Aa are uppercase letters and lowercase respectively, N is a number, and [] are brackets. I consistently get AAAAaaaaaa-NNNN (15 chars) in the database, although if i rename the file so that the path and filename together are less than 50 chars, it works without a problem. The path is 35 chars.
One thing I've noticed which may not be related at all is that when I go in to edit a parameter i've previously created, it doesn't show the data type I previously selected, it always shows the first in the list (BigInt). If I reselect varchar and choose ok, then go back to edit the param again, it always still shows bigint. It may be that this is stored correctly and just not showing correctly in the drop down, but I thought i'd mention it.