SpannerMonkey(smce)

You can find the KSP.Log in the main ksp folder.  It will tell me instantly what your issue is , although i suspect you have installed the mod incorrectly . When installed correctly the file path should be KSP/GameData/BDArmory.    If it's anything else the mod will only be partly functional , as almost everything is expecting the files to be at that location

an image below of a typical weapon mod install GameData folder

Is there a chance that you could help guide me in installing the mod myself because I just wanted to start fresh, and I deleted Ksp and am now redownloading it at the moment. Could you give me links for everything I need in order to redownload KSP properly? 

Well the BDA you got from the right place . 

and you'll also need https://github.com/jrodrigv/PhysicsRangeExtender/releases/download/1.6.0/PhysicsRangeExtender.1.6_03182018.zip

which is needed for BDA,

and module manager https://ksp.sarbian.com/jenkins/job/ModuleManager/lastSuccessfulBuild/artifact/ModuleManager-3.0.7.zip

you can see all of those installed correctly in the image posted earlier .  Anything else you wish to install is your choice, i would suggest however before piling in more mods, that you try the game with just those above ,

you will find BDA craft in the craft folder in the BDA mod, these are ready to use and are kept up to date with the mod these can be moved into your game save sph folder when the game is running,  so start the game create a save go to SPH.  minimise the game ,  get the craft from the bda mod folder and drop the craft files into your newly created  save file, then  switch back to the game and open the craft window in the sph and the BDA aircraft and test platforms will be there ready to use.

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