We do not understand this information .. you omnly writing that you are not able to install joomshopping in 1.7.
If you download correct JoomShopping for 1.7 it works without any problems. Might be problems on your server or your server configuration which we do not know.
There are thousands of installations on joomla 1.7 allready and not problems reportet yet.
We also testet it in different installatins before releasing it.
So please check out and change voting because product works fine and we take a lot of afforts in it.