I created my own version of this, but I have an issue with it. The cap for the total ships says the right number in the research area, but in the main interface after I researched it, the number won't go over 2000. The number will go down to -500 or so, but after that, nothing, I can't build any more ships. I changed it so with all upgrades researched, the total is 8000. Any idea what is causing this?