Regardless of what Fuwanovel states, the official homepage for the translation project is probably best:
http://boysofsilencetranslations.wordpress.com/mashiro-iro-symphony/
Well, think of it this way: If you read a book 3 times, that simply shows your interest or at least favor for that title. Even if you can't relate to Visual Novels, if you can think of a book you've read at least 3 times, you'll understand how I feel about this title.
I completely agree that the anime was "rushed"--for both the Akaneiro and Mashifony. Well, I say this because I've played both the VN and watched the anime for both titles and liked the original work over the other...
Regards to the little terms, they are universally accepted acronyms for the respective games. "Akaneiro" for Akaneiro ni somaru saka, "sakusaku" for Koi ga saku koro sakura toki, and "koisaku" is actually an acronym for "Koisaku miyako ni ai no yakusoku wo".
Asians have a tendency to shorten things like this because it's fast and convenient, lol (It's not just the Japanese)
Colorful Pop?
I would actually not buy from eBay because normally, the price is double that of the actual book (plus shipping). Additionally, Colorful Pop is Hisuitei's artbook--not a doujinshi. Simply put, you can go to gelbooru (or whatever image hosting site) and find uploaded scans of Colorful Pop, and make your own "artbook" if you want a personal hard copy.
Personally, I don't like her doujinshi. She had several, but all of them are simply "sketches" compared to other doujinshi out there, and I really think Tsubasu-sensei is only fit for artwork.
On the other hand, it sucks that she doesn't do commissions... I would've LOVED to have her draw a dakimakura for me (not that I already have three 8D)