custom_indicators_not_publishable
What happened
Publishing stores a run you computed on your own machine, together with the version of each custom indicator it used. When Forge cannot pin a version, because it is no longer available, the store is refused with 409.
What to do
Run it again with indicators that are available, then publish that run.
Example
json
{
"error": "This run could not be stored.",
"code": "custom_indicators_not_publishable"
}