I downloaded mine off a torrent that was on this google drive.
ISTA_Standalone - Google Drive
Download the torrent file called "ISTA_Standalone 4.32.1x.no need license". And if you don't know how to download torrents, install application QBittorrent and then you can open the torrent file and that'll download all the files.
Caution, IIRC the torrent includes ISTA+ and ISTA-P (for programming only). So if you only need ISTA+, then on QBittorrent you need to select the files you only need for ISTA+. Look at the text file I attached for list of what folders/files you need exactly (the text file is included in the torrent but thought I might save you the trouble).
I searched for a whole day for a direct download link but couldn't find one other than on Mega.NZ and due to large file size you needed to sign up for a premium account to download all the files because Mega.NZ has daily download limit. I would put the mega.nz link here but turns out that it's for the ISTA version that needs an activation key. So I'll just leave it out in case of confusion for others. The highest ISTA you can download without need of activation key is
4.32.1x
Honestly cannot remember where I found the link to the google drive with the torrents to all the ISTA versions, I think it was from a Bimmerfest link or possibly an automotive coding forum. Thankfully it's still in my browser history. Hope it helps.
