Errors trying to compile sample ZKP code sig_and_vrf_example.rs

[rgutierrez2004]

I'm getting the following errors when trying to compile code sig_and_vrf_example.rs.
Rust version: 1.47.0

ERROR 1
error[E0308]: mismatched types
--> src/main.rs:91:20
|
91 | x: &self.sk.0,
| ^^^^^^^^^^ expected struct zkp::curve25519_dalek_ng::scalar::Scalar, found struct curve25519_dalek::scalar::Scalar
|
= note: expected reference &zkp::curve25519_dalek_ng::scalar::Scalar
found reference &curve25519_dalek::scalar::Scalar

Cargo.tml
...
[dependencies]
zkp = "0.8.0"
rand = "0.7"
curve25519-dalek = { version = "2", default-features = false, features = ["serde", "std"] }

[features]
default = ["u64_backend"]
u32_backend = ["curve25519-dalek/u32_backend"]
u64_backend = ["curve25519-dalek/u64_backend"]
simd_backend = ["curve25519-dalek/simd_backend"]

ERROR 2
Also, if trying using the latest version of rand and curve25519, get a different error:
error[E0277]: the trait bound R: zkp::rand::RngCore is not satisfied
--> src/main.rs:49:34
|
49 | SecretKey(Scalar::random(rng))
| ^^^ the trait zkp::rand::RngCore is not implemented for R
|
::: /home/oracle/.cargo/registry/src/github.com-1ecc6299db9ec823/curve25519-dalek-3.0.2/src/scalar.rs:558:22
|
558 | pub fn random<R: RngCore + CryptoRng>(rng: &mut R) -> Self {
| ------- required by this bound in curve25519_dalek::scalar::Scalar::random
|
help: consider further restricting this bound
|
48 | fn new<R: RngCore + CryptoRng + zkp::rand::RngCore>(rng: &mut R) -> SecretKey {
| ^^^^^^^^^^^^^^^^^^^^

Cargo.toml
...
[dependencies]
zkp = "0.8.0"
rand = "0.8.3"
curve25519-dalek = "3.0.2"