afaik, eScript is a framework for webspeed developed by progress or progress distributor in the uk.
maybe theres some eclipse plugin work done, maybe its the regular progress plugins ?
its a propietary framework and afaik not a very big one, though i don't doubt it saves work and has plenty of benefits.
i dont know if you can just download and start hacking. i doubt it has any documentation or at least well documented.
you probably need to be a company and theres probably some consulting involved to get to use the product.
but you can just call them up and find out.
but why even go there ? and start with frameworks ? start simple
if you need, go over to amazon.com or the book store round corner and get yourself a networking and dhtml, maybe ajax books.
and of course there tons of material and free stuff on the net ...but you get what you pay for, ya know.
heres a link to a cool free site
http://www.dhtmlgoodies.com/