After 76 prolonged OS updates, several re-installs and updating a years old rohan client for an hour and replacing the new dl'ded one.. I no longer have the above issue!
Instead, it now gives me:
The instruction at 0x003425fd referenced memory at 0x003425fd. The memory could not be read.
Click on OK to terminate the program (which also renders my screen resolution at the crappy rohan-login one - yeaaah f.u. too D: )
Considering the fact that I don't have this with any other (much more resource demanding) game, I'll just assume that this memory leak is caused by rohan and not my hard-/software and, evidently, will also assume that I will not make a (short as it would've been) return to the ever darkening (and emptying)world of Rohan (you can read the latter in Saruman's voice). There will be no dawn for ..well, me.