Android Question Library for AR NyARToolKIt

Too less informations to help.
At least without seeing the SLC Settings you used and also the Library code is missing.
I don´t see how one can help here.

In class core.NyARMat you have a field with the name 'clm' and a property with the name 'getClm'. B4X does not like this as the BADdoclet removes the 'get' and 'set' prefixes from properties in the xml file it generates. Rename the field or make it private.

Also make sure you are compiling with Java 8 as BADdoclet can produce bad xml or fail if run under Java 11.

Have you read this carefully, and watched the linked tutorial.
While you have compiled the toolkit you will have difficulty in using it in B4A as you can't always just call any Java method from B4A. In particular constructors of library classes are always called without parameters so you normally need to create a 'wrapper' class that is instantiated when it is Dimmed and also provide one or more Initialize methods that take parameters and call the appropriate constructor of the wrapped class to create an instance of it.