No worries
What I meant by multiply those figures is to multiply 3000 x 2400 by a factor of 2 (for example) so that they are 6000 x 4800.
Just input the new figures and export the map again.
You don't have to multiply them both by 2. You could use 1.5, or if you want it a bit unnecessarily large, 2.5. 2 should be about right
And don't worry about the language barrier. I belief a few of the key members of the PF Team are German, so if you end up having to contact them at any point you might find it easer to communicate than you think