I have now downgraded to 4.3.15 (prior to the updates to the SPSS export), and can confirm the export works properly on this version.

This should be fixed in the latest version. Can check with that please?

I've just run a check with 4.3.25, but unfortunately the export still isn't working properly.

The issue seems to be with trailing string fields on each row (when no more numeric occurs on the row): no delimiters are inserted for those.

To illustrate, the pattern I see, is if the fields to be exported are like this example 12 column row structure. (Calling numbers int, text str for simplicity):
1(int),2(str),3(int),4(int),5(int),6(int),7(str),8(int),9(str),10(str),11(str),12(str)

Then delimiters work up to field 8. However, the strings from position 9 (inclusive) have no delimiters anymore (and so if those fields are empty, nothing is shown at all).
Ie:
123,'foo2',345,456,567,678,'bar7',890'foo9''foo10''foo11''foo12'
(Or, if field 11 and 12 are empty:)
123,'foo2',345,456,567,678,'bar7',890'foo9''foo10'

I can't publish the actual data from this survey, but I could fairly easily reproduce it before. I'll try to get an example up but that may be after the weekend.

Couldn't help myself, so I set up a test now. The above is not correct, but I really can't find the pattern.

I've attached an 2 example survey archives with answers (one with 2 groups, one with 1), and the SPSS export. Note the missing delimiters. In this case, it's for all the fields... I can't find why on some production surveys they partially come up.

,,,,,,,,,1,'06-11-2020 10:59:02',1,'nl','1178055172','jZT2XaO7VQAeK6n','06-11-2020 10:58:36','06-11-2020 10:59:02''foo''bar''foo''bar'111'foo'222'bar''foo'
,,,,,,,,,2,'06-11-2020 10:59:32',1,'nl','617589883','3WInDFdTu0CHBXZ','06-11-2020 10:59:14','06-11-2020 10:59:32''foo'111'bar'222

,,,,,,,,,1,'06-11-2020 11:03:53',1,'nl','1932795011','hqV7jjuAtVf8cYj','06-11-2020 11:03:34','06-11-2020 11:03:53''foo''bar''foo''bar'111'foo'
,,,,,,,,,2,'06-11-2020 11:04:35',2,'nl','1290995659','YvotzLHiViJRfR3','06-11-2020 11:04:11','06-11-2020 11:04:35''foo''bar'111'foo'222'foo''bar'

Ran a test update to 4.3.28, unfortunately still missing delimiters:
,,,,,,,,,1,'06-11-2020 11:03:53',1,'nl','1932795011','hqV7jjuAtVf8cYj','06-11-2020 11:03:34','06-11-2020 11:03:53''foo''bar''foo''bar'111'foo'

So far, 4.3.15 is the last to work correctly for me.

Actually I think this is to do with the setting of $num_fields in application/helpers/export_helper.php

Line 137:
$num_fields = safecount($row);
Change to:
$num_fields = safecount($fields);

Seems, at first glance, to fix the problem.
Counting $row does not actually count all the $fields, and thus once we get to line 260/261, no delimiter is added anymore.

It seems to work here, but I do notice that the newer version exports numerics within quotes. This may be correct; it's rather late now but I'll try to get my SPSS users to check. The number of delimiters, at least, is correct.

I just received user feedback; with the above fix the issue seems fixed.
Obviously I'm not well versed enough in LimeSurvey coding to see if this fix is the correct way to do it, and whether there is no collateral damage. There at least is none that I could see J.

I have applied the above fix to the current 4.3.31 update, and have used it in a live environment. There seem to be no adverse effects, and the SPSS export results are now correct.
The fix seems to make sense to me, looking just at the export_helper.php file. Obviously, my knowledge of the entire package is too limited to guarantee no side effects. But users here have not noticed any.

Update: Now running 4.4.6, this issue is still present and the above fix still works for me without issue.

Fix committed to master branch: http://bugs.limesurvey.org/plugin.php?page=Source/view&id=31282

Thank you for your continuous feedback and not giving up on us. We have now patched this in LS3 and LS4 according to your suggestion.

Fix committed to 3.x-LTS branch: http://bugs.limesurvey.org/plugin.php?page=Source/view&id=31283