Question juridique clé
Whether the appeal had to be heard despite the unpaid advance on costs.
Solution extraite
No; after the advance on costs was not paid within the set and extended deadlines, the court had to refuse entry into the appeal.
Motifs extraits
Under Art. 62 BGG, the appellant must pay an advance on likely court costs. The advance was neither paid after the first order nor after the extension with explicit warning under Art. 62(3) BGG, so the sanctioned consequence of non-entry applied.