[BUG]: Edit Model in Prod produces error when trying to add a new template/transition

[liunelson]

I'm trying to recreate Sabina's SEIRDH & vaccination model in Terarium here:
https://app.terarium.ai/projects/f1ee4461-0707-4715-8087-b571b3a00486/overview

I successfully recreated the base SEIRDH model using the "Create Model from Equations" operator with these equations:

\frac{d S}{d t} = - \beta S I
\frac{d E}{d t} = \beta S I - \alpha E
\frac{d I}{d t} = \alpha E - \delta I - \gamma I
\frac{d H}{d t} = \delta I - \epsilon H - \phi H
\frac{d D}{d t} = \epsilon H
\frac{d R}{d t} = \phi H + \gamma I

I stratified successfully this model using the wizard of the "Stratify Model" operator:

I now need to add a "Natural Conversion" transition between S_u, S_v to represent susceptible people getting vaccinated (i.e. S_u -> S_v).

I first attempted this using the wizard of the "Edit Model" operator by dragging a Natural Conversion template onto the canvas and connecting S_u to A5 and S_v to B5. However, I wasn't able to do that: clicking on S_u port of any existing template and clicking on the A5 port of the new template didn't do anything. Ditto for S_v and B5.

Second, I tried to do this in the notebook using this prompt:

Add a natural conversion from S_u to S_v with the name vaccination with the rate of v * S_u * S_v

But this gave this error: