cannot figure out how to use imperial key 1st mission

[DeusBane]

so as the title says i cannot for the life of me get through the big door, i got the imperial key but alas i cannot use it on anything lol please help, trying to relive this nostalgic experience but i cant even get 5mins into the game haha

[`Hi~Fi.`*MMi*]

https://www.youtube.com/watch?v=5vsH-mYT4-w

[Blamite Delight]

you dont use the key on the big door you use the key to unlock supply crates, you need to head up the lift to the command center and activate the turbolaser then use that to blow open the blast door.