Can you tell me what Moodle version you are using ?
I really don't know to be honest...
When you say that you want the 2 cloze questions "in the same folder" I suppose you want them in the same question category.
Yeah, sorry, that was what I meant. Every time those two cloze question are in the same category or imported under a higher hierarchy one, the same problem happens 

It basically says: "Error importing error Error analyzing XML: No memory in line 679, character 8.
- first way is to import the 2 files as usual so the questions would be in 2 different categories "Membranas. Estructura e importancia" and "Núcleo y transporte nuclear" then after that edit the questions to change the categories to suit your requirements. I did that and had no problem with your questions.
This does work, but I want to send them together if I can.
- the second way is to import the 2 files in the same category, to do that during each xml import, you expand the "General" section on the import page and uncheck the "get category from file" checkbox. I also tried that and had no problem.
This does not work for me unfortunately...
If you want I can send you all these files so you can see if it makes a difference trying to import questions one by one.
Yes please!!!
And thanks again for taking the time helping me 