Phew ! So many questions !
Teen Agent : As far as I know this exists as sharewaree, but I'm always on the look-out, just in case.
Armaeth : I think this exists as a commercially released English version.
Igor : Yes. Commercially released, English.
Piposh : not sure about this one.
Verschollen : English. Still pops up on German eBay.
Heaven's Dawn : Don't know.
Trick Or Treat : I have this. Commercial release. English. Boxed.
Drascula : Only boxed as Spanish, I believe. Jewel-cased rerelease is English.
Riana Rouge : Still available (new), on eBay. English.
Hariboy's Quest : Mine is jewel-cased, with manual, but I'm fairly sure that a box exists. Good kids game. Long game too.
No idea about store sales. There aint no such stores where I be livin'.