Export/import action using a watermark/background pdf - can we use a relative path?

We are using several single user licenses in the company. Those colleagues shall be able to apply stationery to pdf files via an action.

I have created an action which sets this background file. That file is in the same folder as the future merge files, like this:

folder - D:\Templates\Offers

background file - background.pdf

file to be merged - offer_12345.pdf

the exported action - our-stationery.sequ

Now when the action is imported by a colleague, the background.pdf will not be found, even though it's located in the same folder.

Let's have a look into the .sequ file (xml):

<Command name="COMP:AddBackground" pauseBefore="false" promptUser="false">

    <Items>

    <Items name="WaterBackCmd">

        <Item name="ANNOT" type="boolean" value="false"/>

        <Item name="BACKGROUND" type="boolean" value="true"/>

        […]

        <Item name="WATERMARK" type="boolean" value="false"/>

    </Items>

    <Item name="WaterBackCmd_SRC_FILE" type="text" value="Rb-Kopfbogen_Folgeseite.pdf"/>

    <Item name="WaterBackCmd_SRC_PARENT" type="text" value="/D/Templates/Offers/"/>

    </Items>

</Command>

Of course. If my colleague is using a folder C:\Offers, this cannot work.

I have tried to manually empty the WaterBackCmd_SRC_PARTENT value, but that breaks the imported action.

What are the allowed values for the folder?

I cannot believe that there shouldn't be something like "self" or at least a relative path. What sense would it make to export an action if it ist not suitable for collaboration, then?