Yes I'm on 6 and I've have some failed orbital bombs orbiting a planet for centuries (They have 0. 5 thermal sensors or something like that) How do I remove them?

It seems to me like you're trying to make ships and assign them to a task Group that's not over the planet.
That's what happened when I tried doing something like that.

No, it is happening with industrial production too.  On all planets. . . They just keep locked at 0. 00%

Me again guys. . . .
I'm experiencing a problem.  (Yeah another one), My shipyards are acting weird (On all planets and systems) they don't complete any kind of task, it simply stay stuck on 0% and when I pass 30 days for example the estimated completion date just jumps one month.  I've checked events and everything and there are no mineral shortage events or anything related  to shipbuilding.  It started when I tried to make a 100000 ton ship (Yeah 100 thousand).

In class design screen you can select a component and than press "Opso Comp" to make it disappear from the list as obsolete. If you do that to a component you'd rather keep you can go to "View Tech" accessible through the same window find the component, select it and press obsolete again. It should revert it.

If you mean tech you have designed but have not researched yet than in the research tab of the economy window just select the tech and press "delete" right under the list. I think (but I'm not sure) you can only delete racial tech (the one you designed) so there is no risk of removing the research for say "Missile Launcher Reload Rate 6" and such.


As for the sizes of the engines. Civilian jump engines are 10 times bigger than military ones (so if you select size 5 it will be HS 5 for military and HS 50 for civilian). Civilian jump engines if I'm thinking correctly are slightly less efficient than military ones.
easy way to check is to see a size 5 civilian engine [50HS] and size 50 [also 50HS] Military engine that technically is the same size but can transport more, it is however vastly more expensive than the civilian one. Aditionally ships equipped with military engines can only use jump points created by military jump engines and ex aequo for civilian engines.

As for regular engines civilian engines are 5 times bigger than military ones. They have better fuel consumption but much smaller power to mass ratio.
Example
Power Output: 100     Explosion Chance: 5     Efficiency: 1    Thermal Signature: 100
Engine Size: 5 HS    Engine HTK: 2
Cost: 50    Crew: 25
Materials Required: 12.5x Duranium  0x Neutronium  37.5x Gallicite
Power Output: 250     Explosion Chance: 1     Efficiency: 0.1    Thermal Signature: 250
Engine Size: 25 HS    Engine HTK: 1
Cost: 62    Crew: 25
Materials Required: 15.5x Duranium  0x Neutronium  46.5x Gallicite

Military engine gives 100 power per 250 tonnes while civilian one gives only 50 per 250 tonnes. The Civilian engine however has the efficiency of 0.1 to the military 1.
Also it's less likely to explode if hit, but if your ship with a civilian engine is getting hit it's quite probable that it's going to explode anyway.

Only after a xenology team has identified the ruins by sitting at the planet for a while.  For the sake of thorough instruction

All launchers include a magazine for the missile they fire, box launchers included.   Do your fighters have a missile loadout set from their class design window? Did you order them to reload?

Thanks that fixed the problem.  Now I can face the spoiler swarm.  (Already defeated the ancient spoiler)
Another doubt (I'm sorry for my newbness) How do I order a engineer brigade to dig an ancient ruin?

Oh thank you guys, I must be mentaly ill, how I could not see that window. . .
I need help again. . . . . .    Do fighters need magazines? Mine are equiped with box launchers and their carrier has ordnance, but it doesn't load any missiles into them.