This is the documentation of JSU for Jira Server/Data Center. If you are using JSU on Jira Cloud, you can find the documentation here.
The 'Value Field' check will compare the current value of a field against a predefined value. It can compare strings, numbers or option id's. For select fields, you may compare either by string or option id, the latter may be better, as the label of an option may change over time, the id however does not.
If a field can have several values (like components), it is enough, if one of the values matches it.
You must specify the field and value that will be the prerequisite for the check. For example:
If you choose the comparison type String, only '=' and '!=' are valid options.
You may leave value empty and choose comparison type '!=', to tell that a given field is required for the condition.
For date fields without time, use the format 'yyyy-MM-dd' for values, and for those with time 'yyyy-MM-dd HH:mm'.
Example February 12th 2014: 2014-02-12, at 8:05 AM: 2014-02-12 08:05, at 4 PM: 2014-02-12 16:00.
For information on how to configure a check for a workflow transition in JIRA, see the JIRA documentation.
A workflow is configured so that the 'Start Progress' transition has the 'Value Field' check set to 'MultiSelect' = '10021' (option id). A user viewing an issue in that workflow will not see the 'Start Progress' transition unless 'MultiSelect' has at least the option with id '10021' chosen.
Supported Field Types
In its different modules (especially those for workflows), the JSU app supports many different field types. System fields, as well as custom fields.
However you should be aware, that not all field types are supported. Also not in all combinations. We think we cover the most important field types and still are continuously adding and improving which and how different field types are supported. But the one you need, might just not (yet) work. Some custom fields of other third party app might never get supported.
For that reason you should always test anything you do with the JSU app with fields. Before you buy a license for JSU, try it with a free evaluation license, if it works for you.