Hey I really enjoy making new devices, weapons and maps.

but i have stompled upon an issue. I created a device with an negative mass. (Mass = -200.0) designed it and all was good. I've played with for some time. and called it anti-gravity generator. BUT ! sometimes and only sometimes it spontanously explodes taking the whole fort with.... why ?

seems to me that the game doesnt like the negative mass ?! can anyone explain ?
please help.. its an awesome device, when building high ... but the risk..

:) :) peace