Likely Aigis hs problems then because flash is crashing from using up too much memory. As someone who regularly forces flash to crash (via using the chrome task manager and ending the process) when I notice flash getting out of hand, I've never had Aigis stop working on account of flash crashing. As for the question of what software Aigis uses, I'm not entirely sure on the specifics, but a quick look at the html of the webpage shows the game is enclosed in a div labeled "emscripten_border". A quick google search for emscripten brings up the wikipedia page, which notes emscripten is used to compile standard exicutable applications to run as client side web applications. It note that it produces javascript to do this, though also later on notes that certain game engines can be converted to HTML5. As such odds are Aigis runs in one of the two, meaning issues would most likely stem from either Javascript or HTML5. Given there is a script directing to "http://assets.millennium-war.com/00/html/script/game.js" I'm fairly certain javascript at least is involved, though my understanding is HTML5 tends to make use of javascript, so that doesn't rule it out.

Note, this is the same person as before.