Just a quick update.
Following a sugestion by JMM, I inactivated both directx dll files found in histwar root directory, but the error persisted. I then copied the file d3dx9_42.dll (apparently involved in the error...) from my system32 directory to histwar root, but that also did not correct the error...
Well, just add this as another windows idiossyncrasy, I quit...

(why can't the Macs be the gaming machines ??

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(as a side note I found that there are two d3dx9_42.dll files in my PC, one on the system32 folder and another on the Firefox root folder (I checked and it's supposed to be there in Firefox 4.0)...both the same version number, but the Firefox one with a Kb more in size...

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