Sending animated gifs and videos with Microsoft Botbuilder to Skype endpoints - node.js

Question

I am building a bot service to communicate to various endpoints. I have Skype basic communication running through Microsoft Botbuilder in Nodejs. I can send text to the Skype client fine, however when I want to send rich messages with images (animated gifs) or videos, things start going haywire.
1) Sending a animated gif:
function createAnimationCard(session) {
return new builder.AnimationCard(session)
.title('Microsoft Bot Framework')
.subtitle('Animation Card')
.image(builder.CardImage.create(session, 'https://docs.botframework.com/en-us/images/faq-overview/botframework_overview_july.png'))
.media([
{ url: 'http://i.giphy.com/Ki55RUbOV5njy.gif' }
]);
}
I call this code from another function:
exports.sendGif = function sendGif(chatBotUserSession, picUrl, contentType) {
var card = createAnimationCard(chatBotUserSession);
var reply = new builder.Message(chatBotUserSession).addAttachment(card);
_bot.send(reply);
};
When I do this I get to see an image with a play button (in the desktop Skype, mobile client does not show image at all), however pressing the button shows an error "opening not possible". I have tried different gif sources in the url field, but none seem to work. Also tried https for source.
2) I then moved to trying to display a video:
function createVideoCard(session) {
return new builder.VideoCard(session)
.title('Big Buck Bunny')
.subtitle('by the Blender Institute')
.text('Big Buck Bunny (code-named Peach) is a short computer-animated comedy film by the Blender Institute, part of the Blender Foundation. Like the foundation\'s previous film Elephants Dream, the film was made using Blender, a free software application for animation made by the same foundation. It was released as an open-source film under Creative Commons License Attribution 3.0.')
.image(builder.CardImage.create(session, 'https://upload.wikimedia.org/wikipedia/commons/thumb/c/c5/Big_buck_bunny_poster_big.jpg/220px-Big_buck_bunny_poster_big.jpg'))
.media([
{ url: 'http://download.blender.org/peach/bigbuckbunny_movies/BigBuckBunny_320x180.mp4' }
])
.buttons([
builder.CardAction.openUrl(session, 'https://peach.blender.org/', 'Learn More')
]);
}
When I call this using:
exports.sendMovie = function sendMovie(chatBotUserSession, picUrl, contentType) {
var card = createVideoCard(chatBotUserSession);
var reply = new builder.Message(chatBotUserSession).addAttachment(card);
_bot.send(reply);
};
It all works... at least on my desktop Skype. My mobile skype (iOS) now crashes each time when I open the chat with my bot...
So two questions:
1) Does anyone know why I can't seem to send animated gifs that actually play?
2) Anyone have experience with bots on mobile Skype sending rich content and consequently crashing the app?
Thanks.