Well I guess you want a GM to answer but I'm on now and I have 2 more cents to add to my earlier 2 cents so I guess yr stuck with MEEEEEEE!!!!! :-P
Well one thing you should know is Win7 is distinctly immune to degraded performance over time as compared to WinXP so in hind sight its prolly NOT yr HD; which seems to point towards yr RO installation. Re-install ^.^
Also; if yr the kind of person who likes to backup all their installs, after fresh installing HeRO you could copy all the patch files as they are downloaded before they are repacked to another folder. Then when you need to install the next time just paste them in yr RO folder before running the patcher. This makes re installing again and again a breeze.
I have in fact experienced exactly the same problem(loading screen occasionally hung) but in my case I fixed it with a clean format and a re install of XP.
More solutions?(yes I'm a total geek)
Two words. System restore. BTW you can also disable system restore on other drives(those which you don't want touched) so as to specifically target say C:/
Since you have Win7 I'm almost certain its not yr drive(however large drives are as a rule more susceptible to instability, way over 30%(YES 30) are returned to Seagate every year for replacement). I'd put my money on a re installation of HeRO but if you STILL experience problems..
(ok this is getting ridiculous but I'm not done)
A great way to benchmark yr system and validate beyond doubt that yr hardware and OS are in top form is to install one of those big BIG games(Resident Evil 5, Starcraft 2, Witcher; or the like xD). NOTHING taxes yr HDD, OS and other hardware like these(especially yr HDD). If there is a problem, it will surface here too enabling easy diagnosis.
Good luck! Hope I helped x3
The struggle to free myself of restraints becomes my very shackles. - Meshuggah