I see that according to the link below that you are supposed to be able to use custom objects for triggers but I can't seem to find documentation on how this is done. Does anyone have any recommendations?
Understanding Marketo Custom Objects - Marketo Docs - Product Docs
Also, these are not SFDC custom objects. We are a financial institution and we track product usage/changes through custom objects.
Do you have the 'Triggers' defined for that 'custom object' in the 'Admin' area?
Read Add/Remove Custom Object Field as Smart List/Trigger Constraints - Marketo Docs - Product Docs
Last couple of screenshots.
Once you 'check' the Trigger flag for a field on the custom object, you can see the 'custom object related' triggers in the smart campaigns
Hope this helps.
The documentation you were looking for must be the one below:
Trigger Off Custom Object Changes - Marketo Docs - Product Docs
You can take a look at it if you are still working on this project.
Hope you will find it useful,
Once you approve a custom object in Marketo, you then get a trigger option for that particular object. "added to "custom object name""
We have a Object that we utilize for asset consumption and the object holds records on all assets we have. We then have a second object that links our leads/contacts to that asset table.
Now that we have the lead attached to an asset they consumed, now we need to build programs for these. We have trigger programs that listen for the connection of the asset table and then adds interesting moments and adds scores. We could add them to programs or whatever we so desire.
In this screen shot you will see the trigger that is firing. "Asset Table SIL" is the name of the custom object in Marketo. The Constraints are based on the fields in the custom object. As you can see I have this trigger looking for assets that include our tag of "application-notes".
Therefore this trigger will catch any lead/contact that downloads an asset with a tag of "application-notes". for this one we simply increase their score, and add an interesting moment.
I hope this helped.