More than a month after St. Cloud launched what analysts say is the country’s first free citywide Wi-Fi network, folks in this 28,000-person Orlando suburb are still paying to use their own Internet service providers as dead spots and weak signals keep some residents offline and force engineers to retool the free system. The same troubles with the small town’s big Internet project could be lessons for municipalities from Philadelphia to San Francisco considering similar networks. St. Cloud officials are spending more than $2 million on a network they see as a pioneering model for freeing local families, schools and businesses from monthly Internet bills. Instead, what they have so far is a work in progress.