Customization plug-in custom fields transport

Hi,
we are currently using Projeqtor version 10.0.3 and customization plug-in version 6.4.
We have a production environment and an UAT one.
As we have try to refresh environment with customization modifications, we have copied files from repository =11.0ptprojeqtor/model/custom=11.0pt from one environment to another.
Every customization is well taken except for custom fields name. How can we take these names to other environment ? Are they somewhere in the database ? an other file ? Is it necessary to recreate them manually each time ?

Thank for your help
best regards