[TYPO3-dam] Exiftool - jpeg xmp meta data extracted but not inserted to mapped fields

[Thorsten Indra]

Dear All,
I am a new here and to Typo3, and am looking for some pointers for XMP meta 
data extraction from jpg headers, using the dam functionality.

I am running the dam indexer, using the service of the exiftool extension.
A TS config (in the media page - see below) should map my custom metadata 
fields extracted by exiftool to fields in tx_dam (tinytext fields I had 
created).

What is working:
    - These fields are visible in the "Extra data" section (under Additional 
meta data/ IPTC) when choosing Media > List > Info
    - The data does successfully get output to the "meta" field in tx_dam
What is NOT working:
- These values are not written to my fields which I have mapped in TS

(Ultimately, this data is to be repurposed in the rgsmoothgallery, for 
localized captions, alt_text, etc.)

I have brooded over the code of the exiftool service for days now and tried 
various changes in the TS, but being a photographer, and not a programmer,
I am not moving forward anymore. Documentation is slim and the web is quite 
silent.

Does anyone have ANY pointers, why the data does not get inserted into these 
columns?  Or am I missing something?
(One possible guess I have is that these new columns I created in tx_dam 
might need to get mapped somewhere in a TCA - but I don't know where and 
how.)

Thanks in advance for any pointers and Best Regards,
Thorsten Indra

PS:  Typo3 v. 4.3.0 | exiftool (v. 0.1.4) | dam 1.1.3 | dam indexer 
(v.1.1.0) | latest exiftool libraries is installed (v8.03)

The TS for the media page follows here:
###################################################
tx_exiftool_sv1 {
 exiftoolparams = -S -scanForXMP -ext .JPG DIR
        # default output of exiftool
  # TIP: not sure if -ALL is still valid parameter - not documented in 
latest lib
  # Orig values were: -S -ALL
 fileCharset = utf-8
    dbCharset = utf-8
 # For debug the devlog will be used,
 # $TYPO3_CONF_VARS['SYS']['enable_DLOG'] = 1;
 # has to be set for that!
 debug = 1
}
 tx_exiftool_sv1.match {
 # field from dam = output from exiftool
## keywords
 keywords = keywords
        keywords.tag.1.splitToken = ,
## category
 # should we look up for category?
  # otherwise they will not be imported
 category.lookUpCategory = 1
 # the Token, how they are separated in meta-data
  category.lookUpCategory.splitToken = ,
  # should we create non existing categorys?
  category.lookUpCategory.insertNew = 1
 category = Tip Web Cat

## other fields
 title = Master Document ID
 file_orig_loc_desc = Master Document ID
 alt_text = Description Tip Caption EN
 caption = Headline
 # sys_language_uid =
 # language = '0'
 copyright = Credit
 keywords = Subject
## my fields
 tx_tip_caption_de = Description Tip Caption DE
 tx_tip_caption_en = Description Tip Caption EN
 tx_tip_headline_de = Description Tip Headline DE
 tx_tip_headline_en = Headline
 tx_tip_origclientid = Managingstock Tip Orig Client ID
 tx_tip_origclientname = Managingstock Tip Orig Client Name
 tx_tip_presprio = Presentation Tip Pres Prio
 sorting = Presentation Tip Pres Prio
 tx_tip_weblocationinfo = Location Tip Web Location Info
}
###################################################