Hello Chris,
FYI. According to Denes Bernad and Charles K. Kliment in Magyar Warriors Vol. I, the Hungarians had three R-35 tanks (formerly Polish-owned). The authors do not provide detailed listing for Soviet equipment captured beyond a few T-20 Komsomolets and have very little info on the AFVs deployed in Budapest in 1945. Best of luck in your search; but it appears you may already got the best source on the subject.
Thanks for chiming in Thierry.
The Renault is an odd duck. With the MA removed, it's
possible that it was a Romanian
Vanatorul de Care R-35 Transformat tank destroyer captured by the Hungarians in 1944. Most likely it was one of four R35 (according to Allied Minor Note 33 and Axis Minor Note 32) that saw action in Poland in 1939 and ended up in Hungarian hands. [Edit: Indeed it was an R35 with a 37mm MA, as shown in the first photo in post 7 below.]
But I'm more interested in learning if the R35 in the photo actually saw combat in Buda. And if so, where and how it and the ex-Russian tanks were employed. According to Mihályi, these AFV were used to backstop an anti-tank ditch that ran along the northern corner of the Vérmező. The photo I initially posted has a ditch of sorts in the foreground, btw. I suspect that this photo was the genesis of a dramatized piece of artwork that depicts Soviet infantry attacking these AFV and a school located, I
think, in AA12 (or BB12), out of frame to the right. The action, if true, struck me as having the makings of a late-war, tin-can scenario. FWIW, the painting shows the Renault armed with a 37mm gun.
And if there's a scenario in here somewhere, how ought a T-30 to be represented, assuming one of the T-60s was in fact a T-30.
Bonne journée!