Hi Cedas
When you have created your tree, can you save it as follows:
File, Export File, Copy/Export Individuals in ?.?.?. Tree. (?.?.?. is whichever tree you are using)
This brings up another box headed "Export Individuals in ?.?.?. Tree". You should then be able to choose where you want to . tree, a name for your tree, and use the 'save as type' drop down to select GEDCOM.
Click Save, and another box should appear headed "Export to GEDCOM".
Click OK (I do not change any of these settings) and your GEDCOM should be saved.
If you want some screen shots of the boxes/screens you hopefully should be getting, PM me with you email address and i'll send something to you.
Good Luck
Nadine