@thehen:
The correct syntaxe for &tvPhx is :
the function displayTV works with the table "tmplvar_contentvalues" which the table where tv values linked to the document are stored. All the tv of the document found will be available for displaying. It’s not necessary to precise any tv name in the snippet call. You need only use the appropriate placeholders of the tv you want displayed in your own template result.
With custom non-Modx table, you could be interested to have the same feature. In this case you will write :
&tvPhx=`myCustomTable:myCustomDisplayField`
where "myCustomTable" is your own joined table and "myCustomDisplayField" your own custom function to display value of your fields. With this table and this function define in the configuration file. I will give an example on the AS demo site later.
Coming back after a summer break, I could now help you if needed. Let me know.