A decent first-quarter report is overshadowed by a weak outlook.Stock investors tend to be a picky lot, and one item they're picky about is a company's financial guidance. It's all well and good to post quarterly results that beat estimates. However, since most market participants are -- sensibly -- more concerned about the future than the past, if a business's forecasts come in under expectations, it can be punished by Mr. Market.That was the case this week with customer acquisition and management-software ...