Welcome to the Star Forum. I'm sorry it seemed that folks were slow to answer and that some of the answers seemed a little bit haughty to you... we're generally a pretty friendly bunch around here. On the subject of using or adapting standard 7/8X14 dies on your Universal, yes it has been done, and if you are a fairly talented machinist you might even be able to make a head to accomplish that. OTOH, the Star was and is the "Rolls Royce" of progressive reloaders and to adapt it to a set of Lee dies would be kinda like adding a Chevy engine to the Rolls... it would work, but would it really be a good thing to do.
My suggestion is to use your press as is and get familiar with its workings and its idiosyncrasies, then decide whether you want to invest in the conversion(s) to other caliber(s) if they are worthwhile for you. Unlike many other reloading tools, the Star is indeed an investment that will continue to be at the same time useful and growing in value. Your Uncle was apparently a wise man in this regard and gave you a fine gift; congratulations.
Regards,
Froggie
PS If and when you DO decide to change calibers or make upgrades, members of this forum like Dave, who has already responded and Bruce, who Dave mentioned, can provide excellent OEM-replacement and well thought out and tested upgrade parts... they've already helped me with my 38 spl (only) Star Progressive.