I have been using the following "special" version of Poderosa for a long time:
Special version 5.7.5 (Nov 20, 2010)
Based on official version 4.1.0
I like this version a lot, mostly because of the Favorites system which lets me bookmark (with passwords) all of my connections. I frequently connect to many machines and this makes it a lot easier.
I see that this version here on Github is based on an older version of Poderosa and does not have the Favorites menu or ability to bookmark connections (with passwords saved). Please consider implementing this here.