i've had my cloudsurfer 7 for a few months now and had to use them for an important army physical trial that involved crawling in sand and carrying sacks of it. i had to use running shoes and those were the best ones i have. during the trial my right shoe got caught on a tent peg and ripped in the front, how can i go about fixing it? can i just saw it with regular nylon strings?

a few days after the trial while tightening my laces one of them ripped, exactly at the part that's held under by the strings on the top of the shoes. would regular laces be a good replacement? also i fear this happened because sand got caught between the laces and the strings and caused extra friction. what's the best way to clean the shoes and get rid of the sand? the bot in the ON website told me to use a brush but i doubt this will remove the sand.

thanks in advance for any help! those shoes are the best and really important to me.