Tried that already but i am unable to as i keep getting a message saying that the file is corrupt
I hope you used 7-Zip to extract, WINRar doesn´t work properly with these files.
Anyway "corrupted files" is the main problem if downloading splitted files - AI R15 are 15 single files, so you have the chance 15 times to get a download failure.
You have to figure out which part is corrupted and download this one again.
Or - that´s the reason why it´s heavily recommended to use torrent download - the big single .7z file is also by far easier to extract/install.
Torrent file for AI R15 here
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Pls note that the "Optional Sideloader Modpack Studio" is ONLY for StudioNEO and NOT for the game. You can deactivate before starting torrent download unless you want to intensively work with StudioNEO.