Compatibility issues with Stack Modifier

having this enabled seems to break the Stack Modifier plugin. When splitting a stack half of it deletes and turns into a single item?

just realized this is meant to have an inbuilt stack modifier which would likely be the issue but how do we edit stack sizes with this?

The screenshots of this plugin (1.0.0) show the stack size edit button but the latest version the button is missing?

just found it hiding in the configuration & train wagon tab fml..

Changed Status from Pending to Not a Bug