To be fair though, this sort of thing is of low evidential value when it comes to assessing the Kercher case. In law (and with justified ethical underpinnings) it shouldn't be relevant to the case that Guede had an alleged prior history of B&E, theft, violence or even of pestering women.
The trials of Knox, Sollecito and Guede should be entirely based on reasoning related solely to the evidence connected directly to the Kercher murder. Prior conduct or "similar pattern" evidence is notoriously dicey legally, and should never be used except in a small number of extreme and unusual circumstances. I don't think it should have been used in this case.
However, what DOES need to be examined is the following: 1) Was Guede physically capable of breaking in via Filomena's window? (in my view: yes, most certainly); 2) Is there any evidence of motive for Guede to break into the girls' cottage: (in my view: yes: he was low on money, due on rent, already on the fringes of trouble with the law); 3) Is the evidence consistent with Guede alone breaking in? (in my view: yes); 4) Did Guede therefore have the means, opportunity and motive to break in via Filomena's window? (in my view, yes).