@ritapearl - Sorry to be so late to the party here. The post with info from NJH is everything I was prepared to recommend. I also saw the YouTube video. Very helpful information. I like the Boost Breeze drinks. They are fruity and light and easy to take with you. Any time I have to put weight back on, I reach for those. I also will snack later in the evening, although if you have acid reflux, I wouldn't recommend it past 7pm. Try to make dinner your biggest meal - you have less time to work off the calories.
As far as staying away from what causes mucous, I'm no help there. I would talk to a nutritionist or Google it. The National Jewish Health site has lots of info as well as the NTM and bronchiectasis sites. @lmartin272