Need Preloader - Animation App Slow

Hello, I'm very very...very new in Adobe Animate and I'm not a programmer of any kind so, let me tell you about a project:

I'm working on an app that is about Tales (animated) for children. Here's the thing: It has like 32 animated scenes and everytime I export it it gets really slow when I test it on the cellphone. It's like loading every frame in the moment and no matter what if it's a simple thing or it has too much motion. After the scene is complete, if I use a "play again" bottom you can see that it's seems fine, really fluently. I wanna know if any of you knows what kind of "PreLoader" can I use to load all scenes at once in the beggining. 

I was looking on google but I only find preloaders for a video or just one frame animation. I only use simple bottoms: foward, play again, menu and options (go and play "scene X" or "scene Y").

Thank you very much!