The V90 SDL went on smoothly here.  
I got USRSDL.EXE from the web site, put it into
an empty directory, and ran it in a DOS window 
to unzip it into several files.
The setup was very nice.  
I found which one I need and got it easily.  
First I ran 'USRSDL.EXE /C=1 /B=57600' as I've 
always done and it told me what to do and, for 
me, there was a DOS .exe and instructions in 
ASCII text, all of which are important.  
Read all the .txts, and so entered 'SDL20.EXE
/C=1', which was right for me.  And so it
installed.
Thanks for the V90, USR.     :)
 * KWQ/2 1.2i * Guelph ON
--- Maximus/2 3.01
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