Your code tries to call &PlxHml::x_log, but your posted source code has:

package PLXHML;
[download]

So, x_log at best lives in PLXHML::x_log.

This somewhat runs counter to your assertion that now all references and filenames are in CamelCase, so maybe you can reduce your code to a short, self-contained example that still exhibits the problem you have.

The next best thing likely is to look at line 47 of PlxHml.pm and see what routine is called there.

Start removing code from PlxHml.pm until you have around 20 lines that reproduce the problem.

Update: I think I have it somewhat wrong - from the log posted above, Plx exports x_log into main::, but nothing exports into PlxHml. But somewhere in PlxHml.pm your code looks like the following:

package PlxHml;
use strict;

sub foo {
    x_log(...);
};
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Most likely, then you will need to import Plx into PlxHml as well:

package PlxHml;
use strict;
use Plx;

sub foo {
    x_log(...);
};
[download]