How to create custom column for meta field

Use tab "Meta" in the table tools popup.

Also you can add it by code. Use next code in file functions.php:

Trough code you can use custom columns in such shortcode [tableon id=49 columns='id,title,__price,hmeta_1']

Also for some tables it is possible to modificate results in the table cell:

This code for table 21 in meta cell meta_1 will display results of a math operation.