I was playing 48 years without this error.
I got the same message whenever i create a new game(sequel or mmo) and its only happens to me in the second office.
Im using cheatmod,expansion pack and “Game Dev Tycoon: Platforms, Events, and Topics, OH MY”.
I’m using "Expansion pack and “Game Dev Tycoon: Platforms, Events, and Topics, OH MY”
Then i think there is a problem with the compability with these 2 mods :(.
We cant do anything else just wait.
Sometimes when i release a game.
I was playing 48 years without this error.
Now i release a game, got error, click “Ok” on error. And i get this error all time if i click on screen. Game restart - all okay.
And i use not only "Expansion pack and “Game Dev Tycoon: Platforms, Events, and Topics, OH MY”
After i release a game and then dont matter where i click, i always got this message.(it means on the ground,my character or my staff).Only solution to solve this for me to save game and restart the game, but its happens again after release anything 
What version of the ExpansionPack and My Mod do you have?
How to i can see version?
P.S All my mods 
you can see the version by loading Game Dev Tycoon and going to the Mods menu
It was probably my mod. I’ve did a small update and it should be fixed now. Could you check it??
Okay, v.1.0.2
Thanks, i update.
I lose part of my researched topics.
I got these error when I edit a Save File , or I did something wrong in the Mod Code .
Like , last time I made an error in the console publish date and retirement date and it made me that error 
So many! 