Hi Silvio,
Have you updated your pg directory from the svn recently (and restarted the server)? I believe the last of the %hash errors was fixed around revision 6504 last november. (It won't be noticed by older perl compilers -- just the latest versions object to that construction.)
http://webwork.maa.org/viewvc/system?view=rev&revision=6504
I wonder if the error about WWPlot is also due to some files in PG being out of date or not being updated properly.
-- Mike
Installation
Error message when opening homework set
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