Unlocks in co-op, does it work like unlocks with mods?

[icer107]

Title is question.
I played the online beta way back (before dataminers depraved us of the second beta ), and used savefile 2, as if to just start at the same place my friends did.

When I asked one of my friends to play again, who in co-op had unlocked a couple characters and items, she didn't have any progress at all.

Does co-op make the game think it's "with mods", i.e. you need to clear Mom once first, before getting further unlocks?

[aywee]

In open beta, unlock progress was limited by the player who had the least of them.
For example, if Payer 1 had Dead God and Player 2 only had everything up to Mega Satan (i.e. no Hush, Delirium and alt floors), then the co-op session will be limited.
I believe, this will be the same in full release.

[icer107]

The problem is, rather than having limited unlocks in co-op during the betas, I asked her to boot up Isaac NOW, and despite having unlocked items and characters during the open beta, none of those unlocks were there now.

We unlocked Laz, Cain, Eve and Azazel during the open beta, and I still have those unlocks on my second file, the one I used during Open Beta, but she does not have those unlocks on her end.

That's why I'm wondering if Co-Op (and by extension the beta) is treated like mods.

[aywee]

All progress in open beta (regardless if it's singleplayer or multiplayer) is stored in separate save files (rep_beta_persistentgamedataX.dat)
You can use this tool to transfer progress from open beta saves to stable saves (rep_persistentgamedataX.dat).
https://old.reddit.com/r/bindingofisaac/comments/18mhtuf/i_wrote_a_fix_for_everyone_who_lost_their/