** Swiss banking software firm Temenos TEMN.S rises 4% after it appointed Takis Spiliopoulos as chief executive officer
** Spiliopoulos, who was the company's CFO since 2019, stepped in as interim CEO in September following previous CEO Jean-Pierre Brulard's ousting
** "While he still needs to build up a track record in leading the company, his appointment should bring stability into the organization and set it up for the next phase of growth," Vontobel ("buy") says
** Temenos' stock is up 18.25% year-to-date
(Reporting by Tristan Veyet)
((Tristan.chabba@thomsonreuters.com))