Hi Raul,
I believe answer to your question regarding the online docu
"I guess it is the sum of all the requirements of the skills og the agent."
is NO.
The skill required level is sum of skills required by the contact, not the agent. The contact can require skills several ways, one of them is through queue skill requirements. Others can be keywords for e-mails contacts, IVR for phone contacts etc.
For the calculation is not important how the skills are acquired. However, for this discussion, we can simplify that the table above shows one queue with three skill requirements.
So to translate to your case, it would look like this:
Contact in Operativa queue:
| Skill | Required skill | Agent skill |
|---|---|---|
| Operativa | 5 | 5 |
| Instalaciones | -/0 | 1 |
| Calculated | 5 | (5+0)/5=1 |
Contact in Instalacion queue:
| Skill | Required skill | Agent skill |
|---|---|---|
| Operativa | -/0 | 5 |
| Instalaciones | 5 | 1 |
| Calculated | 5 | (0+1)/5=0.2 |
At least this is my understanding 
...
Regards,
Dawood.