Adhesion problem (heat bed or extruder issue)
If the first layer is not sticking well to the bed it can be caused by several issues. Usually the height of the first layer plays a significant role as does the flatness of the bed. Temperature can definitely  also play a role; you want the temperature to be close or at the glass transition temperature of the plastic filament when it is in a sort of fluid state. 

Personally I hated the original tape that came with the bed or blue tape I bought separately. Also the surface finish is nowhere close to printing directly onto the Aluminium bed or on a glass plate. For adhesion, a PVA based spray (e.g. hairspray, or more expensive special print spray like 3DLAC or even a glue stick), should be used as it becomes very sticky at elevated temperatures.

The tape can be removed, but should be replaced with something that grips onto the filament, see previous paragraph. I removed the tape after day one I got build my kit and started printing directly onto the Aluminium bed using the sticky spray.

To answer your questions, the following checklist determines the order in which you should solve your issue:


First check the nozzle position relative to the bed; this should ideally be the thickness of a single plain A4 paper.
Make sure the bed is level; what is meant that the bed is relatively level with respect to the nozzle, not water bubble level with respect to the Earth (you'd be amazed to find how many people do that).
Use the correct bed temperature; it is usually found on the tag of the spool of filament. Alternatively, look it up on the internet, or increase it at first with about 5 degrees Celsius at a time.
You could over-extrude a little for the first layer by increasing the extrusion multiplier for the first layer, or add some extra temperature to the extruder (increase with 5 degrees Celsius).
Printing brims or adding mouse ears or discs integrated in your design may also work to create more grip.


And yes you should remove the masking tape before you put the glass on as it would only act as an insulator.