Auto Actions - changing fields before payment

Joomla! 1.5.26
CB 1.8
CBSubs 1.3.0 RC2

I have set up an Auto Action on a Field to prefix an id number with a 9 at Registration to create a membership number. I used the Field Action with the onAfterUserRegistration Trigger. That sets the membership number to 9nnn where the id is nnn.

However, when the CBSubs payment takes place and the item code is created (e.g. S5-997-18 where the id is 997), the prefix has not yet been added, but the prefix is required.

Without a description of the Auto Actions Triggers, I am at a loss to know if there is a Trigger which will add the prefix before the CBSubs item number is created. My guess, and that is all it can be without knowledge of the code, would be StartSaveRegistration or BeforeRegistration.

Can you confirm which, if either, of these will achieve my objective?
Thank you.

CBSubs takes place before the after registration trigger. You may want to try the before registration trigger and see if that'll work. As I can not see the source either your guess is as good as mine. I recommend testing a few of the triggers to see which will do the trick.

I have tried both the BeforeRegistration and StartSaveUserRegistration triggers, but neither ends in the field being updated, let alone being done at the right time.

If anyone can suggest another way of achieving this, I would be grateful. Thanks

Ah, right. There's a bug in CB that'll cause field updates during registration to fail. Please see the below bug ticket.

forge.joomlapolis.com/issues/3354

So can I safely replace my administrator/components/com_comprofiler/library/cb/cb.tables.php
with the version in forge.joomlapolis.com/issues/3354 ,
or should I wait for CB 1.8.1?

Yes, the file included is a pre-patched CB 1.8 file. You'll need to first ensure you've CB 1.8 installed.