i know nothing about your server or site .
turn on debug and find out what the error is….
https://support.wp-pizza.com/topic/how-to-enable-debug-in-wordpress/

i would suggest you have a look at these resources as to how cloudprint works and which printers are compatible (and in what way )

https://www.google.com/cloudprint/
https://support.google.com/cloudprint/answer/1686197?hl=en

other than that , maybe somebody else can help you with your thermal/pos printer.
personally i know nothing about these (and generally cannot comment on hardware anyway)

it’s – most likely – not the plugin but your php settings

see the troubleshooting here
https://support.wp-pizza.com/downloads/wppizza-add-ingredients/
(different plugin but my guess is your problem is exactly this)

add a css background-image somewhere

>So, it was a PayPal issue and they wouldn’t really help,
sounds familiar…it’s always someone else’s fault as far as they are concerned…
in any event , glad it’s working for you again

maybe i misunderstand. However, you said the following:

> I have Pizza Hawaii Prices 6$ (Pick up Prices) and Delivery 6,60$,
> and ex Pizza Parma 7$ (Pick up) and Delivery 8$

so your Hawaii is 6.60 (delivery) 6 (pickup) – i.e discounted by -0.60 on pickup
same for Parma e.g.
8 (delivery) 7 (pickup) – i.e discounted by 1.00 on pickup

so you need to discount those . if you use “cheapest etc” and use the restrictions to only apply the discount to set items, then that cheapest equals that one item.

as your 2 items (Hawaii/Parma) are different and require a different discount you would have to set up 2 separate discounts, set the restrictions to those particular items (also checking the box to restrict to those) and enter appropriate amount.

Again, the simple discount is – essentially – just a “spend [x] (min amount) get y (%/money) off” on the whole order .

Anything more complicated you will need the “cheapest [x]…”
(depending on what you need it to do the label may not always be 100% appropriate for your specific discounts , but there is no way to cater for every single idea/combination you could come up with)

>I think plugin have bug in Simpel Discount

no it hasn’t
simple discounts work exactly like the discounts under wppizza->order settings (just that you can set more of them with a bit more granularity)
i.e the minimum order required for the discount to apply is calculated based on the exclusions (or not as the case may be)

for anythimg more complicated (i.e your scenario described above) you will need to use the “cheapest reduced” using requirements as needed

you could apply discounts with this when it’s pickup (or vice versa)
https://support.wp-pizza.com/downloads/wppizza-coupons-and-discounts/

i also suggest reading this link
https://support.wp-pizza.com/topic/things-to-do-on-first-install/

>Could it be theme related?
absolutely

use the z-index property