Shri Narayan Prasadji,Narayanaya Namah,
I am afraid you will have to make your computer a dual boot system-------one Windows7 that too 32 bit architecture for such DOS based programs.
The other you can continue with Windows8 whether 32 bit or 64 bit for other programs.
You may not however be able to install Windows7, 32 bit if it has Windows8 already, though you can install Windows8 after Windows7 .
No doubt it is a cumbersome process but that is what I had to do and am not having any problems now----best of both the worlds!
Regarding the Peter-Duffet
Smith programs that I have, I will have to check if they have become obsolete as they were based on 1985 version whereas Shri Venktesh Murthyji has been kind enough to give the pointer for 1991 version.
I will get back to you shortly.
Btw, there are quite a few open source programs like Astrolog7.5, Stellarium or even the much touted "Mahabharata" "riddle solver" Planetarium Gold program!
If you are comfortable with VB6, you could use VSOP87,which is not as up to date as Swiss Ephemeris but then it does serve the purpose of dating the events from 10000 BCE up to 10000 CE!
And last but not the least, the Swiss Ephemeris Test page is there for anybody to use, thanks to Shri Dieter Koch and his team and it is the most accurate program as on date without any hassles---that to
o from about 13000 BCE to about 17000 AD---if I am not mistaken!!