Indiana Jones style map

Hi guys another newbie here,
I’ve been looking for the tool to make Indiana Jones map with route animation. Found Synfig, had a quick look onto the tools and tutorials, thought “couldn’t be easier”, well it isn’t so.
I’ve imported map image, drawn nice curvy route across the map with draw tool, created about 10 keyframes, then intuitively I’ve started to remove the activepoints at each of keyframes of the animation. Unfortunately the result is slightly different from what I’ve been looking for, although the last second of animation shows exactly what I would like to achieve. have a look:

I’ve already wasted two evenings trying to figure it out, would you give me any hint what am I doing wrong? I went through the tutorials and videos on youtube but haven’t found anything that would help.

Hello odee,
I think it’s difficult to animate by removing points.
An easier method is to hide the line and show it gradually.
I put a file as an example.

Muhkayoh made too a “Indiana Jones” map :
test.sifz (2 KB)

Nice one mad0 thanks! To be honest i’ve been trying to use masking but I didn’t quite understand all the types of blend methods, so I stuck at some point. Now I can move on with the project. Cheers!