Hi, is there a sure way to play SP a biome?

I have the improved portal, I've cast the multiplayer spell on it, the biome selection window opens, together with the choice between pvp/cooperative and invite friend check box.

I went with 'invite friend', nobody joined once and it worked, I was alone in a Biome.

I tried again, it did not work.

any suggestion?

thanks!!!

To use the MP feature for SP this is what works for me:

1: You must run the game through gog galaxy.
2: when you get to the MP menu, pick the one map you want to play on, make it the first map in the group, select coop and invite friend(that makes it not do rando internet matches).
3: when you are at the invite friends menu (kicks you to galaxy) just click the X in the upper right to close it.
4: you are now back in the game and will just have to wait for the "invite friend/search for player" to fail/time out.
5: when it does it says it failed to find anyone for you and asks you if you want to go alone, cancel out(no), or retry the search. Just click yes (i want to go alone) and in you go.

It works reliably for me. I'd guess maybe just be sure to wait long enough on the time out, which might go/up down in length with patches.