Hi,
1. I don't see the fields shifting either on my end, even though I'm also using chrome. Maybe they need to clear their browser's cache ? If only two persons get the problem and no one else, it has to be someone with their setup. Did you ask them to try with another browser ?
2. The size of the input boxes being not correct comes from the CSS:
input[type="text"], input[type="password"], input[type="email"], input[type="url"], input[type="color"], input[type="date"], input[type="datetime"], input[type="datetime-local"], input[type="month"], input[type="number"], input[type="range"], input[type="tel"], input[type="time"], input[type="week"], textarea {
width: 90%;
padding: 4px 0;
color: #3D5166 !important;
font-size: 14px;
font-family: Verdana, Geneva, Arial, Helvetica, Sans-Serif;
font-weight: normal;
font-style: normal;
text-shadow: none;
}
of your template. This has nothing to do with the update.
3. The text "Login or continue as a guest" can be changed with a translation override, as you must already know by now:
www.hikashop.com/download/languages.html#modify
4. If you want to remove the submit and register buttons, you can add such CSS:
.hikabtn_checkout_fields_submit, .hikabtn_checkout_login_register { display:none;}
These display because they allow you to submit only that block without submitting the whole page. This allows merchants to have true "one page checkouts", which was not possible before as the whole page had to be submitted.
5. Please understand that HikaShop 3 is a major release. You're not supposed to directly update production websites with it but instead try it first on a copy of the website (best practices even recommend that you do that for each update of something on your website). Remember that we changed the whole add to cart and checkout systems for HikaShop 3. It's bound to have some differences with previous versions and templates made for previous versions of HikaShop would have to be adapted (even though it's usually not much).