Errors importing External Metadata into ERSDA18.3

I'm trying to import .ldm and .dbm models from IBM Information Data Architect into ERSDA18.3  and I'm receiving fatal import messages:

I have several .ldm files that received the following error messages:

<FATAL> Exception: java.lang.NullPointerException
<FATAL> MITI.MIRException: [MBCM_E0045] The model could not be imported.
<ERROR> [JBDG_F0006] The Java process did not complete successfully
<INFO> MITI component(s) with build version '10.0.1 - 2019-09-18': Mimb.jar
<ERROR> The tool failed with error code ERROR_IMPORT

And another .ldm model that received the following error messages:

<FATAL> Exception: java.lang.NoClassDefFoundError: org/eclipse/gmf/runtime/common/core/command/ICommand
<FATAL> MITI.MIRException: [MBCM_E0045] The model could not be imported.
<ERROR> [JBDG_F0006] The Java process did not complete successfully
<INFO> MITI component(s) with build version '10.0.1 - 2019-09-18': Mimb.jar
<ERROR> The tool failed with error code ERROR_IMPORT

I cannot seem to find any info on how to resolved these errors. Any guidance would be appreciated.