RDF Causal - error when running gen_forecast

I am working somewhat outside my core competency trying to get a causal forecast to run.

Using the GA 16.0.3.30 RDF configuration. Loaded a promo indicator, weekly sales.

Can run the rdf_gen_forecast.ksh with -l 01  (week/item/store, AutoES) without problems.

But when running rdf_gen_forecast.ksh with -l 07 (week/item/store, Causal), I get the following error:

<E 2018Nov13 17:07:10.490> Exception thrown during batch forecast - IllegalParse: Parse of - methmasktmp07xb=if(>0,reqmth07xb,7) resulted in syntax error at 19.

The expression is something that gets created on the fly as part of that batch script. It's not configured and therefore out of my control.