when I download wtc file ,I select SDK version -> 8.5, but when I download from email ,it's not a wtc fle ,it's a png file.
In general the SDK supports 2 options --> .wtc file approach and the .zip file approach (which especially if you work with our Expert Edition the .zip, or plain approach brings advantages). You can find a comparison of these two here:
But also our professional addition allows you to work with plain images (starting with SDK 8.5).
If you want to download a .wtc file, please choose the option 6.0 - 8.x.
Thx and greetings