If the intake camshaft position sensor was in fact replaced, was an OEM camshaft position sensor used or an aftermarket sensor?
Also if a BMW specific code reader is being used, sometimes you get more specific details about the sensor circuit, such as an open or a short?
Maybe there is a wiring problem to the sensor, loose terminals in the connector, or maybe a non OEM sensor was used? I cannot tell you for sure that non OEM sensors are bad or not wise to use, but I have read many reports that suggest that OEM sensors are the best to use.
If the fuel pump is an issue, usually you can turn the key on and off a few times before you start the car to pressurize the fuel rail even if the there is problem with the fuel line bleeding down. If a fuel line leakage is an issue, the key on and off 3-4 times to prime the fuel line will result in a more immediate start. This may give you some idea if fuel line pressure loss is a problem.
On a side note, fuel pumps are problems in these cars, you might check the history to see if a pump has ever been replaced.