Erebus1985 There's no way to force the game to install from disc, unfortunately. But even if you could, it wouldn't help you much. The game has changed so much from when your disc was produced that the patches alone would likely overrun your data limit. The App allows people to play offline without patching, but only after the game has been launched while online once, and to be launched online, it needs to be fully updated. So you'd trade one problem for another.
Do you have access to a different computer that has an updated version of Sims 4 installed? If so, you could copy the files from that computer to yours using an external device. This wouldn't fully install the game—it would never launch in this state–but telling the EA App to "download" to the location where the files are would allow the App to simply verify the files and finalize the installation. That would at least limit the amount of data you'd need to download, perhaps enough for your needs.
This isn't completely reliable, in that the App sometimes chooses to redownload one or more packs, but you could watch for that and cancel the download if necessary. You could try copying that pack over again, and if it didn't work, you're not required to play with all packs installed anyway.
