Here some info you can post on your github site:
Do to incompatiblity issues with Economy Release, In order to use SE Toolbox with Space Engineers you are required to roll back to version 1.191
In order to roll back, right-click Space Engineers on steam then select Properties then goto BETA Tab and change to 1.191 and press close. Once Steam changes to 1.191 you will need to create a new world as current ones will not be compatible. You can now place your blueprint (any new blocks beyond 1.191 will not be placed). Save the world and exit Space Engineers and start SE Toolbox to do any changes you need to do, since the current installation of Space Engineers is 1.191 SE Toolbox will functions normaly.